Loading...
HomeMy WebLinkAbout20190313 Skidmore Swing Bldg SWPPP The LA GROUP 4G Long Alley p 518-587-8100 Saratoga Springs 1:518-587-0180 NY 12866 www.thelagroup.corn Landscape Architecture'a Engineering P.C. Stormwater Pollution Prevention Plan Prepared in accordance with NYS DEC General Permit GP-0-15-002 for: Skidmore College Swing Building 815 North Broadway Saratoga Springs, NY 12866 Owner/Operator(s): Skidmore College 815 North Broadway Saratoga Springs, NY 12866 Contact: Dan Rodecker (518) 580-5860 SWPPP Contact(s): The LA Group, PC 40 Long Alley Saratoga Springs, NY 12866 1-518-587-8100 1-518-587-0180 SWPPP Preparation Date: April 12, 2019 Table of Contents 1.0 PERMIT OVERVIEW AND REQUIREMENTS 1 1.1 PERMIT OVERVIEW 1 2.0 SWPPP REVIEW, UPDATE 2 2.1 SWPPP REVIEW 2 2.2 SWPPP UPDATE 2 3.0 SITE ASSESSMENT, EVALUATION AND PLANNING 3 3.1 PROJECT LOCATION 3 3.2 PRE-DEVELOPMENT CONDITIONS 3 3.3 PROJECT TYPE 3 3.4 PROJECT SCOPE 3 3.5 HISTORIC PRESERVATION DETERMINATION/ENDANGERED SPECIES 3 3.6 RECEIVING WATERS 3 3.7 SOILS 4 4.0 EROSION AND SEDIMENT CONTROL 4 4.1 EROSION AND SEDIMENT CONTROL PRACTICES 4 4.2 EROSION AND SEDIMENT CONTROL DRAWINGS 4 4.3 CONSTRUCTION PHASING PLAN AND SEQUENCE OF OPERATIONS 4 4.4 EROSION AND SEDIMENT CONTROL PRACTICE MAINTENANCE 5 4.5 EROSION AND SEDIMENT CONTROL INSPECTION 6 4.6 CONTRACTOR SEQUENCE FORM 7 5.0 POST CONSTRUCTION STORMWATER MANAGEMENT PRACTICES 7 5.1 STORMWATER MANAGEMENT CONTROLS 7 5.2 GREEN INFRASTRUCTURE PRACTICES/RUNOFF REDUCTION TECHNIQUES 7 5.3 POST CONSTRUCTION STORMWATER MANAGEMENT DRAWINGS 8 5.4 HYDRAULIC AND HYDROLOGIC ANALYSIS 8 5.5 COMPARISON OF PRE AND POST CONSTRUCTION STORMWATER RUNOFF 9 6.0 POST CONSTRUCTION STORMWATER MAINTENANCE 9 6.1 MAINTENANCE TO BE PERFORMED 9 7.0 CONSTRUCTION WASTE 11 8.0 OFFSITE VEHICLE TRACKING 11 9.0 TEMPORARY STABILIZATION FOR FROZEN CONDITIONS 11 10.0 SPILL PREVENTION PRACTICES 12 11.0 CERTIFICATIONS 16 12.0 DEFINITIONS 21 Appendices A Notice of Intent (NO I) B Stormwater Management Report and Hydro CAD C Map Set — Location Map and Construction Drawing D SWPPP Inspection Forms —SWPPP Inspection Report E Other SWPPP Forms — Construction Sequence, SWPPP Plan Changes, Spill Response Form, Stormwater Management Practice Maintenance Log F SPDES General Permit GP-0-15-002 G Historic Preservation/Endangered Species Documentation H Deep Ripping and De-compaction (DEC, 2008) Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 1 .0 PERMIT OVERVIEW AND REQUIREMENTS 1.1 Permit Overview This Stormwater Pollution Prevention Plan (SWPPP) is prepared to inform the landowner and construction personnel of the measures to be implemented for controlling runoff and pollutants from the site during and after construction activities. The objective of this plan is to comply with the New York Department of Environmental Conservation (NYSDEC) State Pollutant Discharge Elimination System (SPDES) General Permit for Stormwater Discharges from Construction Activities, Permit No. GP- 0-15-002 requirements. Any material conflicts between this plan and the site plans, specification or instructions, must be brought to the attention of the design professional. The project may have other permits and it is the responsibility of the owner and contractor to know and understand all permits. The operator will be issued a bill from New York State for a one hundred and ten dollar ($110.00) annual fee for the open GP-0-15-002 permit. The operator will also be billed by New York State for a one time one hundred and ten dollar ($110.00) per acre fee for the proposed disturbed soil area listed in the NOI, and finally a one time six hundred and seventy five ($675.00) per acre fee for the proposed increased impervious area listed in the NOI. The operator is responsible to maintain onsite in a secure location that is accessible during normal working hours to an individual performing a compliance inspection, the following information: ✓ the Notice of Intent (NOI), ✓ the NYS Department of Environmental Conservation NOI Acknowledgement Letter, ✓ the SWPPP, ✓ a copy of the General Permit (included in the SWPPP), ✓ MS4 SWPPP Acceptance Form (where applicable), and ✓ All inspection reports. All post-construction stormwater management facilities must be inspected annually by a qualified professional, a report prepared and submitted to the City Engineer documenting the inspections as well as the maintenance activities that were completed during the prior year. Technical standards are detailed in the "New York State Standards and Specifications for Sediment and Erosion and Sediment Control (November 2016)", as well as illustrated on the Construction Drawings included in Appendix C. The design of post- construction stormwater control practices follow the guidance provided by "New York State Stormwater Management Design Manual." The LA GROUP Landscape nrzhdectu«&EnqiFleer,ngYi Page 1 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project# 2018135 2.0 SWPPP REVIEW, UPDATE 2.1 SWPPP Review Applicable Federal, State, and local regulatory agencies that have jurisdiction may elect to review this SWPPP and notify the permittee in writing that the SWPPP does not meet the requirements of their regulations. If the SWPPP needs to be revised, the permittee and the site contractor will make the required modifications within seven days of such notification and submit written certification to the notifying agency that the changes have been implemented. A copy of the SWPPP will be kept available on site for review by regulatory agencies, engineers, and subcontractors. This Project is in the City of Saratoga Springs which is a regulated MS4 community, so a copy of this SWPPP was sent to the City for review. A copy of the signed MS4 Acceptance form is provided in Appendix A of this SWPPP. 2.2 SWPPP Update The permittee identified in this SWPPP shall amend the SWPPP under the following conditions: ✓ Whenever the current provisions prove to be ineffective in minimizing pollutants in stormwater discharge from the site ✓ Whenever there is a change in design, construction or operation that could have an effect on the discharge of pollutants ✓ To address issues or deficiencies identified during an inspection by the qualified inspector, the Department or other regulatory authority ✓ To identify a new subcontractor that will implement any part of the SWPPP. If modifications are required to the post-stormwater management practices and the Project is within a regulated, traditional land use control MS4, the owner or operator of the Project must notify the MS4 in writing of any planned amendments or modifications to the post-construction stormwater management practice component of the SWPPP. Unless otherwise notified by the MS4, the owner or operator shall have the SWPPP amendments or modifications reviewed and accepted by the MS4 prior to commencing construction of the post-construction stormwater management practice. The SWPPP PLAN CHANGES, AUTHORIZATION, AND CHANGE CERTIFICATION form (Appendix E) must be filled out and a copy retained onsite during construction. If modifications are required to the post-stormwater management practices and the Project is not within a Regulated, Traditional Land Use Control MS4, the changes shall be documented in the SWPPP kept onsite. The LA GROUP Landscape Arthdecture dY Engineering Pi Page 2 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project# 2018135 3.0 SITE ASSESSMENT, EVALUATION AND PLANNING 3.1 Project Location The Project is located on Skidmore College's campus, 815 North Broadway, in the City of Saratoga Springs, Saratoga County, NY 12866. See Appendix C for a general site location map. 3.2 Pre-Development Conditions The site is located in the northeast corner of Skidmore College's campus. The site is comprised of lawns, forest, existing parking areas and paths, and existing stormwater features. 3.3 Project Type This project is considered new development. Any increases in impervious area at the site have been designed in accordance with Chapter 4 of the NYSDEC Stormwater Management Design Manual and NYSDEC's General Permit (GP-0-15- 002) for construction activities. 3.4 Project Scope The Project's intent is to construct a multiuse building in the northeast corner of the Skidmore College campus. This includes selective clearing and grubbing of an area east of the North Woods parking lot, construction of the multiuse or "Swing" building, construction of a fire access road and new paths, and expansion of the existing stormwater wet pond. The site developments described herein will result in a net increase in impervious area within the Project's watershed. 3.5 Historic Preservation Determination/Endangered Species The project area is not within an area that might possibly contain archeologically sensitive resources. A letter stating no effect is provided in Appendix G The Project will have no impact on any listed, proposed to be listed, threatened or endangered species, or a critical habitat. The NYSDEC no effect letter is provided in Appendix G. 3.6 Receiving Waters Runoff from the site discharges into a roadside swale, which is conveyed to the City of Saratoga Springs closed drainage system offsite. Ultimately runoff discharges to an unnamed stream. The LA GROUP Landscape Arthdecture dY Engineering Pi Page 3 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 3.7 Soils According to the Natural Resources Conservation Service (NRCS) Soil Survey, the project site area is comprised of Farmington and Galway soil types. The hydrological soil group (HSG) classification for these soil types is D and C, respectively. 4.0 EROSION AND SEDIMENT CONTROL 4.1 Erosion and Sediment Control Practices Temporary Structural Practices ✓ Silt Fence ✓ Dust Control ✓ Stabilized Construction Entrance ✓ Inlet Protection Permanent Structural Controls ✓ Grading ✓ Rock Outlet Protection Temporary Stabilization Practices (including vegetative practices) ✓ Seed and mulch bare soil areas within 14 days of disturbance unless construction will resume in that area within 21 days. Permanent Stabilization Practices (including vegetative practices) ✓ Seed and mulch all disturbed areas. Slopes that are 3:1 or steeper should receive a Rolled Erosion Control Product (RECP), sodding, and or hydro- seeding a homogenous mixture of wood fiber mulch with tackifying agent. Refer to Construction Drawings attached in Appendix C for detailed information on each practice. 4.2 Erosion and Sediment Control Drawings Erosion and Sediment Control practices are shown on Construction Drawings included in Appendix C. 4.3 Construction Phasing Plan and Sequence of Operations ✓ Temporary structural erosion controls will be installed prior to earthwork as per the attached plans. ✓ Areas to be undisturbed for more than 14 days will be temporarily stabilized by seeding. The LA GROUP Landscape nrzhhectu«&EnqiFleer,ngYi Page 4 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project# 2018135 ✓ Disturbed areas will be reseeded and mulched immediately after final contours are re-established and no more than 14 days after the completion of construction at that site. ✓ Temporary erosion control devices will not be removed until the area served is stabilized by the growth of vegetation and the area is certified as being stabilized by the Erosion Control Superintendent. Construction Activities Start - Stop Sequence must include major items such as, but not limited to, clearing and grubbing, excavation and grading, utility and infrastructure installation and any other activity resulting in soil disturbance. Include installation of erosion and sediment control practices and timing of installation. Install silt fence and construction entrance Week 1 Selective clearing and grubbing. Weeks 2-4 Construction of new fire access road. Weeks 4-6 Building and path construction. Weeks 5-16 Monitor/maintain erosion and sediment control measures Ongoing Remove erosion and sediment control measures upon Once final stabilization has stabilization of contributing areas been reached. 4.4 Erosion and Sediment Control Practice Maintenance ✓ Silt fence — maintenance shall be performed as needed and material removed when "bulges" develop in the silt fence. ✓ Stabilized construction entrance — entrance shall be maintained in a condition which shall prevent tracking. This may require periodic top dressing with additional aggregate. All sediment tracked onto or spilled on public rights of way shall be removed immediately. When necessary, wheels must be cleaned to remove sediment prior to entrance on public rights of way. When washing is required, it shall be done in an area stabilized with aggregate and wash water shall be directed away from streams or wetlands preferably to a broad grassed area or a stormwater pond. ✓ Rock outlet protection — once a riprap outlet has been installed, the maintenance needs are very low. It should be inspected after high flows for evidence of scour beneath the riprap. Repair should be immediate. ✓ Replace top-soil, mulch and seed where seeding has been disturbed. The LA GROUP Landscape Arthhecture dY Engineering Pi Page 5 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project# 2018135 4.5 Erosion and Sediment Control Inspection ■ It is recommended that a rain gage be installed at the site. ■ A qualified inspector shall conduct an assessment of the site prior to the commencement of construction and certify in an inspection report that the appropriate erosion and sediment controls described in the SWPPP and required by GP-0-15-002 have been adequately installed to ensure overall preparedness of the site for commencement of construction. ■ This qualified inspector must be a Licensed Professional Engineer, Certified Professional in Erosion and Sediment Control (CPESC), Registered Landscape Architect, or someone working under the direct supervision of, and at the same company as, the licensed Professional Engineer or Registered Landscape Architect, provided they have received 4 hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Department endorsed entity. After receiving the initial training, the qualified inspector shall receive 4 hours of training every 3 years. ■ The day-to-day erosion control activities on the site will be monitored by the construction manager. The qualified inspector (as defined by the NYS DEC SPDES regulations) and his crews will make at least one inspection every seven (7) days of erosion control devices, and non-stabilized areas during construction. A maintenance inspection report will be completed by the qualified inspector after each inspection. The report form to be completed by the inspector is attached in Appendix D. Reports should be compiled and maintained on-site in the SWPPP 3-ring binder. ■ All measures will be maintained in good working order; if repair is necessary, it will be initiated within 24 hours of report. The qualified inspector shall take photographs of any needed repairs and also photograph when the repairs are completed. These photographs will be time and date stamped and attached to the weekly inspection report. ■ Seeded and planted areas will be inspected for bare spots, washouts, and healthy growth. If necessary, spot reseeding or sodding will be implemented. ■ A trained contractor will be an employee from the contracting company responsible for the implementation of the SWPPP. This person will be onsite when any soil disturbing activities are being conducted. The trained contractor must have received 4 hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Department endorsed entity. After receiving the initial training, the qualified inspector shall receive 4 hours of training every 3 years. This trained contractor cannot conduct The LA GROUP Landscape Arthdecture dY Engineering Pi Page 6 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 the regular SWPPP compliance inspections unless they meet the qualified inspector qualifications. 4.6 Contractor Sequence Form The operator shall prepare a summary of construction status using the Construction Sequence Form (included in Appendix E) once every month. Significant deviations to the sequence and reasons for those deviations (i.e. weather, subcontractor availability, etc.), shall be noted by the contractor. The schedule shall be used to record the dates for initiation of construction, implementation of erosion control measures, stabilization, etc. A copy of this table will be maintained at the construction site and updated. 5.0 POST CONSTRUCTION STORMWATER MANAGEMENT PRACTICES 5.1 Stormwater Management Controls The proposed Post Construction Stormwater Management controls on this project are listed below: ✓ Wet Pond 5.2 Green Infrastructure Practices/Runoff Reduction Techniques The proposed Green Infrastructure practices or Standard Management practices with Runoff Reduction capabilities on this project are listed below: ✓ Bioretention Area The provided runoff reduction volume (RRv) is 0.02 ac-ft, which is equal to the minimum required RRv, 0.02 ac-ft. Soil Restoration Excessively compacted areas and areas of cut and fill on the Project Site will have soil restoration applied as needed and as specified in the table below. Attached in Appendix H is "Deep Ripping and De-compaction, (DEC 2008)." This methodology should be followed for soil restoration as specified in the table below: The LA GROUP Landscape nrzhdectu«&EnqiFleer,ngYi Page 7 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project# 2018135 Type of Soil Disturbance Soil Restoration Requirement Comments/Examples Minimal Soil Disturbance Restoration not permitted Preservation of Natural Features Areas where topsoil is stripped Restoration not required Clearingand Grubbing only-no change in grade n g HSG A&B HSGC&D Areas of cut and fill apply 6 inches of Aerate*and apply topsoil 6 inches of topsoil Heavy traffic areas onsite HSG A&B HSGC&D (especially in a zone 5-25 feet around buildings,but not within a Aerate and apply 6 Apply full Soil 5 foot perimeter around inches of topsoil Restoration** foundation walls) Keep construction equipment from Areas where Runoff Reduction Restoration not required,but may be crossing these areas. To protect and/or infiltrationpractices are applied to enhance the reduction newly installed practice from any ongoing construction activities applied specified for appropriate practices construct a single phase operation fence area. *Aeration includes the use of machines such as tractor-drawn implements with coulters making a narrow slit in the soil,a roller with many spikes making indentations in the soil,or prongs which function like a mini-subsoiler **Per'Deep Ripping and Decopmpaction,DEC 2008" • If compost amendment is required, 2 to 4 inches of screened compost will be incorporated into the soil. • Prior to application of the deep-ripping and de-compaction, the depth to bedrock or naturally occurring hardpan should be known so that the depth of tillage be adjusted according to those restrictive depths. • Soils with a slope that exceeds 10% will not have full soil restoration with deep-ripping and de-compaction due to potential for erosion from tilled soil. • Any soil tillage (deep or shallow) will not be done on soils that are excessively wet, as this will damage the soil. • Any tillage will not be done within approximately 10' of the drip-line of any existing established trees. • Any large stones that are unearthed during tillage should be removed from the surface prior to final surface preparation and vegetation establishment. 5.3 Post Construction Stormwater Management Drawings Post construction stormwater management controls are shown on Construction Drawings included in Appendix C. 5.4 Hydraulic and Hydrologic Analysis The program utilized for quantifying stormwater runoff rates and volumes was HydroCAD software, produced by Applied Microcomputer Systems of Chocorua, The LA GROUP Landscape Architecture dY Engineering f'.C. Page 8 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 NH. The SCS 24-hour Type II design storms for 1, 10, and 100-year frequency rainfall were analyzed. ✓ Hydrologic/hydraulic analysis for all structural components of the stormwater control system for the applicable design storms (see Appendix B). ✓ Comparison of post-development stormwater runoff conditions with pre- development conditions (see Appendix B). ✓ Dimensions, material specifications and installation details for each post- construction stormwater control practice (see Appendix B and C). 5.5 Comparison of Pre and Post Construction Stormwater Runoff Stormwater Quantity. These calculations are based on the HydroCAD analysis. Pre Development Post Development 10 year, 24 hour storm (Qp) 32.53 cfs 26.63 cfs 100 year, 24 hour storm (Qf) 94.93 cfs 94.26 cfs Water Quality Volume Calculations The following was utilized to determine water quality volume: WQv= (P) (Rv)(A) 12 Where: WQv= Water Quality Volume (acre/feet) P = 90% Rainfall Event Rv = 0.05 + 0.009(1) where I is impervious cover in percent A = Subcatchment area in acres Required Provided Water Quality Volume (WQv) 0.06 AC FT 0.06 AC FT 6.0 POST CONSTRUCTION STORMWATER MAINTENANCE 6.1 Maintenance to be Performed Skidmore College will be responsible for the continuous upkeep and maintenance of all post construction stormwater management facilities. Post-construction maintenance for this project will consist of regular inspections of permanent stormwater management facilities and steep slopes. These maintenance procedures are essential to assure continual performance of the The LA GROUP Landscape nrzhhectu«&EnqiFleer,ngYi Page 9 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project# 2018135 stormwater management practices on your site. During the inspection and any maintenance activity to the stormwater management practices, the responsible party should fill out an inspection and maintenance log (Appendix E) to record that it was done. Annual inspections of the post construction stormwater management practices shall be completed and inspection reports shall be sent to the office of the City Engineer for their records. The City of Saratoga Springs shall approve a formal maintenance and inspection agreement in accordance with City Code Chapter 242 for stormwater management facilities to ensure the practices will be properly operated and maintained in accordance with the long term operation and maintenance plans. This agreement shall be binding on all subsequent land owners and recorded in the office of the County Clerk as a deed restriction on the property. Catch Basins (All) ■ Sediment removal with a vacuum truck should be done at least once a year, preferably after spring runoff and then in early fall, or when they are at 50% capacity, whichever comes first. ■ Any mechanical valves should be operated for inspection every two months. Stormwater Pond (Wet Pond) ■ Should be inspected twice a year and after heavy rain storms. ■ Any erosion or scour occurring in the pond, forebay or outlets shall be repaired and re-vegetated as needed. ■ Sediment removal in the forebay shall occur every five to six years or when 50% full. ■ Provide maintenance easement and right-of-way and removable trash rack on principal spillway. ■ Regular litter control to be performed as needed. Bioretention Area ■ Clean trash and debris out of system as necessary ■ Dead or diseased vegetation should be replaced ■ When the filtering capacity of the filter diminishes substantially (when water ponds for more than 48 hours), the top few inches of discolored material shall be removed and be replaced with fresh material. The removed sediments shall be disposed of in an acceptable manner (i.e. landfill). ■ Silt and sediment should be removed from the filter bed when the accumulation exceeds one inch. ■ Areas devoid of mulch shall be re-mulched on an annual basis The LA GROUP Landscape Arthdecture dY Engineering Pi Page 10 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 7.0 CONSTRUCTION WASTE Waste Materials: All waste materials generated during construction will be disposed at a suitable landfill, or transfer station. Hazardous Waste: The project will not be a generator of hazardous waste and it is not anticipated that any hazardous waste will be generated during construction. If there are any materials generated, a licensed hazardous waste carrier will be contracted to dispose the hazardous material at a suitable disposal site. If hazardous materials are discovered during construction, the work will be stopped until the issue is resolved. Waste: Portable sanitary facilities will be made available to construction personnel and will be serviced regularly. 8.0 OFFSITE VEHICLE TRACKING Excavation equipment involved with the construction will remain on the project site and will not regularly egress or ingress the site. Any trucks used to bring in materials or remove materials via municipal paved roads will do so over a stabilized construction entrance. If any off-site vehicle tracking occurs, the contractor will be directed to initiate, street sweeping program in the immediate vicinity of the site. 9.0 TEMPORARY STABILIZATION FOR FROZEN CONDITIONS The following temporary stabilization measures MUST be performed when construction is occurring during winter/frozen ground conditions. The following requirements do not supercede any other requirements of this SWPPP as they apply to non-frozen ground conditions. • Perimeter erosion control MUST still be installed prior to earthwork disturbance as per this SWPPP. • Any areas that cannot be seeded to turf by October 1 or earlier will receive a temporary seeding. The temporary seeding will consist of winter rye seeded at the rate of 120 pounds per acre (2.5 pounds per 1,000 square feet) or stabilized as per the temporary stabilization for winter construction/frozen conditions. • Any area of disturbance that will remain inactive for a period of 14 consecutive days MUST be mulched. This includes any previously disturbed areas that are covered with snow. • Mulch MUST consist of loose straw applied at the rate of 2 to 3 bales (90 to 100 pounds) per thousand square feet. • Mulch MUST be applied uniformly over the area of bare soil or bare soil that is covered with snow. For the latter condition, mulch MUST be applied on top of snow. The LA GROUP Landscape nrzhdectu«&EnqiFleer,ngYi Page 11 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 ■ The construction manager or his designee will inspect regularly to ensure proper use and disposal of materials on site. ■ The contractor shall prohibit washing of tools, equipment, and machinery in or within 100 feet of any watercourse or wetland. ■ All above grade storage tanks are to be protected from vehicle damage by temporary barriers. Inventory for Pollution Prevention Plan The materials and substances listed below are expected to be on-site during construction. ■ Petroleum for fueling vehicles will be stored in above ground storage tanks. Tanks will either be steel with an enclosure capable of holding 110% of the storage tank volume or of a Con -Store, concrete encased type typically employed by NYSDOT. Hydraulic oil and other oils will be stored in their original containers. Concrete and asphalt will be stored in the original delivery trucks. ■ Fertilizer may be stored on site in its original container for a short period of time prior to seeding. Original containers will be safely piled on pallets or similar devices to protect from moisture. ■ Paints and other similar materials will be stored in their original containers and all empty containers will be disposed of in accordance with label directions. ■ Portable sanitary facilities, which contain chemical disinfectants (deodorants) will be located on-site, with the disinfectants held in the tank of the toilet. Hazardous Products These practices are used to reduce the risks associated with hazardous materials. Products will be kept in original containers unless they are not re- sealable. Original labels and material safety data sheets will be retained; they contain important product information. If surplus product must be disposed of, manufacturers' or local and State recommended methods for proper disposal will be followed. Spill Prevention The following product specific practices will be followed on site. Petroleum Products: ■ Construction personnel should be made aware that emergency telephone numbers are located in this SWPPP. LCM1 The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Page 13 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 ■ The contractor shall immediately contact NYSDEC in the event of a spill, and shall take all appropriate steps to contain the spill, including construction of a dike around the spill and placing absorbent material over this spill. ■ The contractor shall instruct personnel that spillage of fuels, oils, and similar chemicals must be avoided and will have arranged with a qualified spill remediation company to serve the site. ■ Fuels, oils, and chemicals will be stored in appropriate and tightly capped containers. Containers shall not be disposed of on the project site. ■ Fuels, oils, chemicals, material, equipment, and sanitary facilities will be stored/located away from trees and at least 100 feet from streams, wells, wet areas, and other environmentally sensitive sites. ■ Dispose of chemical containers and surplus chemicals off the project site in accordance with label directions. ■ Use tight connections and hoses with appropriate nozzles in all operations involving fuels, lubricating materials or chemicals. ■ Use funnels when pouring fuels, lubricating materials or chemicals. ■ Refueling and cleaning of construction equipment will take place in parking areas to provide rapid response to emergency situations. ■ All on-site vehicles will be monitored for leaks and receive regular preventative maintenance to reduce the chance of leakage. Any vehicle leaking fuel or hydraulic fuel will be immediately scheduled for repairs and use will be discontinued until repairs are made. Fertilizers: ■ Fertilizer will be stored in its original containers on pallets with water resistant coverings. ■ Proper delivery scheduling will minimize storage time. ■ Any damaged containers will be repaired immediately upon discovery and any released fertilizer recovered to the fullest extent practicable. Paints: ■ All containers will be tightly sealed and stored when not required for use. ■ Excess paint will not be discharged to the storm water system or wastewater system, but will be properly disposed of according to manufacturers' instructions or State and local regulations. Concrete Trucks: ■ Concrete trucks will be allowed to wash out or discharge surplus concrete or drum wash water only at designated locations on site. LC)M The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Page 14 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 Asphalt Trucks: ■ Asphalt trucks shall not discharge surplus asphalt on the site. Spill Control Practices In addition to the good housekeeping and material management practices discussed in the previous sections of this plan, the following practices will be followed for spill prevention and cleanup. The construction manager or site superintendent responsible for the day-to-day site operations will be the spill prevention and cleanup coordinator. He will designate at least three other site personnel who will receive spill prevention and cleanup training. These individuals will each become responsible for a particular phase of prevention and cleanup. The names of responsible spill personnel will be posted in the material storage area and in the onsite construction office or trailer. ■ Manufacturers' recommended methods for spill cleanup will be clearly posted and site personnel will be made aware of the procedures and the location of the information and cleanup supplies. Any spill in excess or suspected to be in excess of two gallons will be reported to the NYSDEC Regional Spill Response Unit. Notification to the NYSDEC (1-800-457-7362) must be completed within two hours of the discovery of the spill. ■ Materials and equipment necessary for spill cleanup will be kept in the material storage area onsite. Equipment and materials will include but not be limited to absorbent pads, brooms, dust pans, mops, rags, gloves, goggles, activated clay, sand, sawdust, and plastic and metal trash containers specifically for this purpose. ■ All spills will be cleaned up immediately after discovery. ■ The spill area will be kept well ventilated and personnel will wear appropriate protective clothing to prevent injury from contact with spilled substance. ■ Spills of toxic or hazardous material will be reported to the appropriate State or local government agency, regardless of the size LOM The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Page 15 Stormwater Pollution Prevention Plan 11.0 CERTIFICATIONS Skidmore College Swing Building The LA Group Project # 2018135 Preparer Certification of Compliance with Federal, State, and Local Regulations This Stormwater Pollution Prevention Plan was prepared in accordance with the New York State Department of Environmental Conservation SPDES General Permit for Stormwater Discharges from Construction Activities (Permit No. GP -0-15-002), pursuant to Article 17, Titles 7, 8 and Article 70 of the Environmental Conservation Law. This SPDES General Permit implements the Federal Clean Water Act pertaining to stormwater discharges. Name: Signature: Doug Heller Title: Civil Engineer Company Name: The LA Group, PC Owner Pollution Prevention Plan Certification Date: 1 certify under penalty of law that this document and all attachments were prepared under my direction or supervision to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who are directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. 1 am aware that false statements made herein are punishable as a Class A misdemeanor pursuant to Section 210.45 of the Penal Law. 1 understand that GP -0-15-002 requires site inspections be conducted by a qualified professional once every seven (7) days and when approved in writing by the NYSDEC, disturbances of greater than five (5) acres at one time require site inspections two (2) times every seven (7) days. These inspections shall be performed by a qualified professional as defined by the General Permit. The Owner/Operator will be held financially responsible for any and all fines related to work tasks that are not specified by the Contractors)/Subcontractor(s) below. Name: Signature: Company Name: L0M The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Title: Date: Page 16 Stormwater Pollution Prevention Plan Contractor and Subcontractor Certification Skidmore College Swing Building The LA Group Project # 2018135 1 hereby certify that 1 understand and agree to comply with the terms and conditions of the SWPPP and agree to implement any corrective actions identified by the qualified inspector during a site inspection. 1 also understand that the owner or operator must comply with the terms and conditions of the New York State Pollutant Discharge Elimination System ("SPDES') general permit for storm water discharges from construction activities and that it is unlawful for any person to cause or contribute to a violation of water quality standards. Furthermore, 1 understand that certifying false, incorrect or inaccurate information is a violation of the referenced permit and the laws of the State of New York and could subject me to criminal, civil and/or administrative proceeding. Name Title Signature Date Company Name Address City, State, Zip Phone Number Lcm) The LA GROUP Landscape Architecture & Engineering P C. Page 17 1. 2. SWPPP Components You 3. Are Responsible For 4. 5. 6. Name of Trained Individual Responsible for SWPPP Implementation Title Signature of Trained Individual Responsible for SWPPP Implementation Date Lcm) The LA GROUP Landscape Architecture & Engineering P C. Page 17 Stormwater Pollution Prevention Plan Contractor and Subcontractor Certification Skidmore College Swing Building The LA Group Project # 2018135 1 hereby certify that 1 understand and agree to comply with the terms and conditions of the SWPPP and agree to implement any corrective actions identified by the qualified inspector during a site inspection. 1 also understand that the owner or operator must comply with the terms and conditions of the New York State Pollutant Discharge Elimination System ("SPDES') general permit for storm water discharges from construction activities and that it is unlawful for any person to cause or contribute to a violation of water quality standards. Furthermore, 1 understand that certifying false, incorrect or inaccurate information is a violation of the referenced permit and the laws of the State of New York and could subject me to criminal, civil and/or administrative proceeding. Name Title Signature Date Company Name Address City, State, Zip Phone Number LOM The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Page 18 1. 2. SWPPP Components You 3. Are Responsible For 4. 5. 6. Name of Trained Individual Responsible for SWPPP Implementation Title Signature of Trained Individual Responsible for SWPPP Implementation Date LOM The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Page 18 Stormwater Pollution Prevention Plan Contractor and Subcontractor Certification Skidmore College Swing Building The LA Group Project # 2018135 1 hereby certify that 1 understand and agree to comply with the terms and conditions of the SWPPP and agree to implement any corrective actions identified by the qualified inspector during a site inspection. 1 also understand that the owner or operator must comply with the terms and conditions of the New York State Pollutant Discharge Elimination System ("SPDES') general permit for storm water discharges from construction activities and that it is unlawful for any person to cause or contribute to a violation of water quality standards. Furthermore, 1 understand that certifying false, incorrect or inaccurate information is a violation of the referenced permit and the laws of the State of New York and could subject me to criminal, civil and/or administrative proceeding. Name Title Signature Date Company Name Address City, State, Zip Phone Number Lcm) The LA GROUP Landscape Architecture & Engineering P C. Page 19 1. 2. SWPPP Components You 3. Are Responsible For 4. 5. 6. Name of Trained Individual Responsible for SWPPP Implementation Title Signature of Trained Individual Responsible for SWPPP Implementation Date Lcm) The LA GROUP Landscape Architecture & Engineering P C. Page 19 Stormwater Pollution Prevention Plan Contractor and Subcontractor Certification Skidmore College Swing Building The LA Group Project # 2018135 1 hereby certify that 1 understand and agree to comply with the terms and conditions of the SWPPP and agree to implement any corrective actions identified by the qualified inspector during a site inspection. 1 also understand that the owner or operator must comply with the terms and conditions of the New York State Pollutant Discharge Elimination System ("SPDES') general permit for storm water discharges from construction activities and that it is unlawful for any person to cause or contribute to a violation of water quality standards. Furthermore, 1 understand that certifying false, incorrect or inaccurate information is a violation of the referenced permit and the laws of the State of New York and could subject me to criminal, civil and/or administrative proceeding. Name Title Signature Date Company Name Address City, State, Zip Phone Number Lcm) The LA GROUP Landscape Architecture & Engineering P C. Page 20 1. 2. SWPPP Components You 3. Are Responsible For 4. 5. 6. Name of Trained Individual Responsible for SWPPP Implementation Title Signature of Trained Individual Responsible for SWPPP Implementation Date Lcm) The LA GROUP Landscape Architecture & Engineering P C. Page 20 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 12.0 DEFINITIONS Construction Activity(ies) - means any clearing, grading, excavation, filling, demolition, or stockpiling activities that result in soil disturbance. Clearing activities can include, but are not limited to, logging equipment operation, the cutting and skidding of trees, tree removal, stump removal and/or brush removal. Construction activity does not include routine maintenance that is performed to maintain the original line and grade, hydraulic capacity, or original purpose of a facility. Construction Phasing Plan - a plan designed to construct particular portions of an individual project at different times. Phasing is often used when a project is very large to limit the disturbance at a single time to 5 acres per phase. Erosion and Sediment Control Practices — temporary measures installed prior to construction and maintained during construction to temporarily treat any stormwater runoff. Once construction is completed and post -construction stormwater management practices are installed and the site is stabilized, the erosion and sediment control practices are removed from the site. Final Stabilization - means that all soil disturbance activities have ceased and a uniform, perennial vegetative cover with a density of eighty (80) percent over the entire pervious surface has been established; or other equivalent stabilization measures, such as permanent landscape mulches, rock rip -rap or washed/crushed stone have been applied on all disturbed areas that are not covered by permanent structures, concrete pavement. Green Infrastructure — in the context of stormwater management, the term green infrastructure includes a wide array of practices at multiple scales to manage and treat stormwater, maintain and restore natural hydrology and ecological function by infiltration, evapotranspiration, capture and reuse of stormwater, and establishment of natural vegetative features. On a regional scale, green infrastructure is the preservation and restoration of natural landscape features, such as forests, floodplains and wetlands, coupled with policies such as infill and redevelopment that reduce overall imperviousness in a watershed or ecoregion. On the local scale green infrastructure consist of site and neighborhood specific practices and runoff reduction techniques. Such practices essentially result in runoff reduction and or establishment of habitat areas with significant utilization of soils, vegetation, and engineered media rather than traditional hardscape collection, conveyance and storage structures. Some examples include green roofs, trees and tree boxes, pervious pavement, rain gardens, vegetated swales, planters, reforestation and protection and enhancement of riparian buffers and floodplains. Impervious Area (Cover) - means all impermeable surfaces that cannot effectively infiltrate rainfall. This includes paved, concrete and gravel surfaces (i.e. parking lots, driveways, roads, runways, and sidewalks); building rooftops, and miscellaneous impermeable structures such as patios, pools, and sheds. LC)M The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Page 21 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 Municipal Separate Storm Sewer (MS4) — a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains): i. Owned or operated by a state, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law) having jurisdiction over disposal of sewage, industrial wastes, stormwater, or other wastes, including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the CWA that discharges to surface waters of the State. ii. Designed or used for collecting or conveying stormwater iii. Which is not a combined sewer iv. Which is not part of a Publicly Owned Treatment Works (POTW) as defined at 40 CFR 122.2. Notice of Intent — a standardized format notification sent to the NYSDEC to inform them of the proposed activity to be sent after the SWPPP has been completed. Owner or Operator — means the person, persons or legal entity which owns or leases the property on which the construction activity is occurring; and/or an entity that has operational control over the construction plans and specifications, including the ability to make modifications to the plans and specifications. Post -Construction Stormwater Management Practices — permanent devices constructed or installed onsite to treat stormwater from a site when construction is completed. Qualified Inspector — means a person that is knowledgeable in the principles and practices of erosion and sediment control, such as a licensed Professional Engineer, Certified Professional in Erosion and Sediment Control (CPESC), Registered Landscape Architect, or other Department endorsed individual(s). It can also mean someone working under the direct supervision of, and at the same company as, the licensed Professional Engineer or Registered Landscape Architect, provided that person has training in the principles and practices of erosion and sediment control. Training in the principles and practices of erosion and sediment control means that the individual working under the direct supervision of the licensed Professional Engineer or Registered Landscape Architect has received four (4) hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Department endorsed entity. After receiving the initial training, the individual working under the direct supervision of the licensed Professional Engineer or Registered Landscape Architect shall receive four (4) hours of training every three (3) years. It can also mean a person that meets the Qualified Professional qualifications in addition to the Qualified Inspector qualifications. Qualified Professional — means a person that is knowledgeable in the principles and practices of stormwater management and treatment, such as a licensed Professional Lc)m The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Page 22 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 Engineer, Registered Landscape Architect or other Department endorsed individual(s). Individuals preparing SWPPPs that require the post -construction stormwater management practice component must have an understanding of the principles of hydrology, water quality management practice design, water quantity control design, and, in many cases, the principles of hydraulics. All components of the SWPPP that involve the practice of engineering, as defined by the NYS Education Law (see Article 145) , shall be prepared by, or under the direct supervision of, a professional engineer licensed of practice in the State of New York. Regulated, Traditional Land Use Control MS4 - means a city, town, or village with land use control authority that is required to gain coverage under New York State DEC's SPDES General Permit for Stormwater Discharges from Municipal Separate Stormwater Sewer Systems (MS4s). Sequence of Operations — the individual steps and their specific order which are undertaken in order to construct a project or a given phase of a project from beginning to end. (i.e. clearing, grading, foundation work, landscaping, etc.) State Pollutant Discharge Elimination System (SPDES) —means the system established pursuant to Article 17 of the Environmental Conservation Law (ECL) and 6 NYCRR Part 750 for issuance of permits authorizing discharges to the waters of the state. Stormwater Pollution Prevention Plan (SWPPP) - a report that is compiled providing detailed information about the proposed activity and the specifics to how the stormwater will be managed during construction and after construction is completed. Surface Waters of the State - shall be construed to include lakes, bays, sounds, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, inlets, canals, the Atlantic Ocean, within the territorial seas of the state of New York and all other bodies of surface water, natural or artificial, inland or coastal, fresh or salt, public or private (except those private waters that do not combine or effect a junction with natural surface or underground waters), which are wholly or partially within or bordering the state or within its jurisdiction. Waters of the state are further defined in 6 NYCRR Parts 800-941. Temporary Stabilization — means that exposed soil has been covered with material(s) as set forth in the technical standard, New York Standards and Specifications for Erosion and Sediment Control, to prevent the exposed soil from eroding. The materials can include, but are not limited to, mulch, seed and mulch, and erosion control mats (e.g. jute twisted yarn, excelsior wood fiber mats). Trained Contractor —means an employee from a contracting (construction) company responsible for the day to day implementation of the SWPPP. The trained contractor must have received 4 hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Lc)m The LA GROUP Land scape h rc h ii eau re & E ng itieering V C Page 23 Stormwater Pollution Prevention Plan Skidmore College Swing Building The LA Group Project # 2018135 Department endorsed entity. After receiving the initial training, the qualified inspector shall receive 4 hours of training every 3 years. It can also mean an employee from the contracting (construction) company that meets the qualified inspector qualifications (e.g. licensed Professional Engineer, Certified Professional in Erosion and Sediment Control (CPESC), Registered Landscape Architect, or someone working under the direct supervision of, and at the same company as, the licensed Professional Engineer or Registered Landscape Architect, provided they have received 4 hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Department endorsed entity. G:AProj-2018\2018135_Skidmore_Flex_Building\2018135Enviro\02SWPPP\201258_SWPPP.docx Lcm) The LA GROUP Page 24 Appendix A Notice of Intent (NOI) 4/12/2019 Project In Relation to Cross Street North Tax Map Numbers Section -Block -Parcel 152-1-3 Tax Map Numbers NONE PROVIDED 1. Coordinates NYSDEC eBusiness Portal System - View Submission Provide the Geographic Coordinates for the project site. The two methods are: - Navigate to the project location on the map (below) and click to place a marker and obtain the XY coordinates. - The "Find Me" button will provide the lat/long for the person filling out this form. Then pan the map to the correct location and click the map to place a marker and obtain the XY coordinates. Navigate to your location and click on the map to get the X,Y coordinates 43.095777,-73.78233180000001 Project Details 2. What is the nature of this project? New Construction 3. Select the predominant land use for both pre and post development conditions. Pre -Development Existing Landuse Institutional/School Post -Development Future Land Use Institutional/School 3a. If Single Family Subdivision was selected in question 3, enter the number of subdivision lots. NONE PROVIDED 4. In accordance with the larger common plan of development or sale, enter the total project site acreage, the acreage to be disturbed and the future impervious area (acreage)within the disturbed area. *** ROUND TO THE NEAREST TENTH OF AN ACRE. *** Total Site Area (acres) 25 Total Area to be Disturbed (acres) 3.4 Existing Impervious Area to be Disturbed (acres) 0 Future Impervious Area Within Disturbed Area (acres) 0.7 5. Do you plan to disturb more than 5 acres of soil at any one time? No 6. Indicate the percentage (%) of each Hydrologic Soil Group(HSG) at the site. https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 3/12 4/12/2019 A (%) 0 B (%) 0 C (%) 64 D (%) 36 7. Is this a phased project? No NYSDEC eBusiness Portal System - View Submission 8. Enter the planned start and end dates of the disturbance activities. Start Date 07/01/2019 End Date 06/30/2020 9. Identify the nearest surface waterbody(ies) to which construction site runoff will discharge. Unnamed stream 9a. Type of waterbody identified in question 9? Stream/Creek Off Site Other Waterbody Type Off Site Description NONE PROVIDED 9b. If "wetland" was selected in 9A, how was the wetland identified? NONE PROVIDED 10. Has the surface waterbody(ies in question 9 been identified as a 303(d) segment in Appendix E of GP -0-15-002? No 11. Is this project located in one of the Watersheds identified in Appendix C of GP -0-15-002? No 12. Is the project located in one of the watershed areas associated with AA and AA -S classified waters? No If No, skip question 13. 13. Does this construction activity disturb land with no existing impervious cover and where the Soil Slope Phase is identified as an E or F on the USDA Soil Survey? No If Yes, what is the acreage to be disturbed? NONE PROVIDED 14. Will the project disturb soils within a State regulated wetland or the protected 100 foot adjacent area? No 15. Does the site runoff enter a separate storm sewer system (including roadside drains, swales, ditches, culverts, etc)? https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 4/12 4/12/2019 NYSDEC eBusiness Portal System - View Submission Yes 16. What is the name of the municipality/entity that owns the separate storm sewer system? Saratoga Springs 17. Does any runoff from the site enter a sewer classified as a Combined Sewer? No 18. Will future use of this site be an agricultural property as defined by the NYS Agriculture and Markets Law? No 19. Is this property owned by a state authority, state agency, federal government or local government? No 20. Is this a remediation project being done under a Department approved work plan? (i.e. CERCLA, RCRA, Voluntary Cleanup Agreement, etc.) No Required SWPPP Components 21. Has the required Erosion and Sediment Control component of the SWPPP been developed in conformance with the current NYS Standards and Specifications for Erosion and Sediment Control (aka Blue Book)? Yes 22. Does this construction activity require the development of a SWPPP that includes the post -construction stormwater management practice component (i.e. Runoff Reduction, Water Quality and Quantity Control practices/techniques)? Yes If you answered No in question 22, skip question 23 and the Post -construction Criteria and Post -construction SMP Identification sections. 23. Has the post -construction stormwater management practice component of the SWPPP been developed in conformance with the current NYS Stormwater Management Design Manual? Yes 24. The Stormwater Pollution Prevention Plan (SWPPP) was prepared by: Professional Engineer (P.E.) SWPPP Preparer The LA Group Contact Name (Last, Space, First) Doug Heller Mailing Address 40 Long Alley Saratoga Springs State NY Zip 12866 Phone 518-587-8100 https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 5/12 4/12/2019 dheller@thelagroup.com Download SWPPP Preparer Certification Form NYSDEC eBusiness Portal System - View Submission Please take the following steps to prepare and upload your preparer certification form: 1) Click on the link below to download a blank certification form 2) The certified SWPPP preparer should sign this form 3) Scan the signed form 4) Upload the scanned document Download SWPPP Preparer Certification Form Please upload the SWPPP Preparer Certification - Attachment NONE PROVIDED Comment: NONE PROVIDED Erosion & Sediment Control Criteria 25. Has a construction sequence schedule for the planned management practices been prepared? Yes 26. Select all of the erosion and sediment control practices that will be employed on the project site: Temporary Structural Check Dams Silt Fence Stabilized Construction Entrance Storm Drain Inlet Protection Biotechnical None Vegetative Measures Mulching Seeding Sodding Permanent Structural Land Grading Rock Outlet Protection Other NONE PROVIDED Post -Construction Criteria * IMPORTANT. Completion of Questions 27-39 is not required if response to Question 22 is No. 27. Identify all site planning practices that were used to prepare the final site plan/layout for the project. Preservation of Undisturbed Area 27a. Indicate which of the following soil restoration criteria was used to address the requirements in Section 5.1.6("Soil Restoration") of the Design Manual (2010 version). All disturbed areas will be restored in accordance with the Soil Restoration requirements in Table 5.3 of the Design Manual (see page 5-22). 28. Provide the total Water Quality Volume (WQv) required for this project (based on final site plan/layout). (Acre-feet) 0.06 29. Post -construction SMP Identification https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 6/12 4/12/2019 NYSDEC eBusiness Portal System - View Submission Use the Post -construction SMP Identification section to identify the RR techniques (Area Reduction), RR techniques(Volume Reduction) and Standard SMPs with RRv Capacity that were used to reduce the Total WQv Required (#28). Identify the SMPs to be used by providing the total impervious area that contributes runoff to each technique/practice selected. For the Area Reduction Techniques, provide the total contributing area (includes pervious area) and, if applicable, the total impervious area that contributes runoff to the technique/practice. Note: Redevelopment projects shall use the Post -Construction SMP Identification section to identify the SMPs used to treat and/or reduce the WQv required. If runoff reduction techniques will not be used to reduce the required WQv, skip to question 33a after identifying the SMPs. 30. Indicate the Total RRv provided by the RR techniques (Area/Volume Reduction) and Standard SMPs with RRv capacity identified in question 29. (acre-feet) 0.02 31. Is the Total RRv provided (#30) greater than or equal to the total WQv required (#28)? No If Yes, go to question 36. If No, go to question 32. 32. Provide the Minimum RRv required based on HSG. [Minimum RRv Required = (P) (0.95) (Ai) / 12, Ai=(s) (Aic)] (acre-feet) 0.02 32a. Is the Total RRv provided (#30) greater than or equal to the Minimum RRv Required (#32)? Yes If Yes, go to question 33. Note: Use the space provided in question #39 to summarize the specific site limitations and justification for not reducing 100% of WQv required (#28). A detailed evaluation of the specific site limitations and justification for not reducing 100% of the WQv required (#28) must also be included in the SWPPP. If No, sizing criteria has not been met; therefore, NOI can not be processed. SWPPP preparer must modify design to meet sizing criteria. 33. SMPs Use the Post -construction SMP Identification section to identify the Standard SMPs and, if applicable, the Alternative SMPs to be used to treat the remaining total WQv (=Total WQv Required in #28 - Total RRv Provided in #30). Also, provide the total impervious area that contributes runoff to each practice selected. NOTE: Use the Post -construction SMP Identification section to identify the SMPs used on Redevelopment projects. 33a. Indicate the Total WQv provided (i.e. WQv treated) by the SMPs identified in question #33 and Standard SMPs with RRv Capacity identified in question #29. (acre-feet) 0.06 Note: For the standard SMPs with RRv capacity, the WQv provided by each practice = the WQv calculated using the contributing drainage area to the practice - provided by the practice. (See Table 3.5 in Design Manual) 34. Provide the sum of the Total RRv provided (#30) and the WQv provided (#33a). 0.06 35. Is the sum of the RRv provided (#30) and the WQv provided (#33a) greater than or equal to the total WQv required (#28)? Yes If Yes, go to question 36. If No, sizing criteria has not been met; therefore, NOI can not be processed. SWPPP preparer must modify design to meet sizing criteria. 36. Provide the total Channel Protection Storage Volume (CPv required and provided or select waiver (#36a), if applicable. CPv Required (acre-feet) NONE PROVIDED CPv Provided (acre-feet) NONE PROVIDED https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 7/12 4/12/2019 NYSDEC eBusiness Portal System - View Submission 36a. The need to provide channel protection has been waived because: Reduction of the total CPv is achieved on site through runoff reduction techniques or infiltration systems. 37. Provide the Overbank Flood (Qp) and Extreme Flood (Qf) control criteria or select waiver (#37a), if applicable. Overbank Flood Control Criteria (Qp) Pre -Development (CFS) 32.53 Post -Development (CFS) 26.63 Total Extreme Flood Control Criteria (Qf) Pre -Development (CFS) 94.93 Post -Development (CFS) 94.26 37a. The need to meet the Qp and Qf criteria has been waived because: 38. Has a long term Operation and Maintenance Plan for the post -construction stormwater management practice(s) been developed? Yes If Yes, Identify the entity responsible for the long term Operation and Maintenance Skidmore College 39. Use this space to summarize the specific site limitations and justification for not reducing 100% of WQv required (#28). (See question #32a) This space can also be used for other pertinent project information. The full WQv is not reduced due to shallow depth to ledge to seasonal high groundwater. Post -Construction SMP Identification Runoff Reduction (RR) Techniques, Standard Stormwater Management Practices (SMPs) and Alternative SMPs Identify the Post -construction SMPs to be used by providing the total impervious area that contributes runoff to each technique/practice selected. For the Area Reduction Techniques, provide the total contributing area (includes pervious area) and, if applicable, the total impervious area that contributes runoff to the technique/practice. RR Techniques (Area Reduction) Round to the nearest tenth Total Contributing Acres for Conservation of Natural Area (RR -1) NONE PROVIDED Total Contributing Impervious Acres for Conservation of Natural Area (RR -1) NONE PROVIDED Total Contributing Acres for Sheetflow to Riparian Buffers/Filter Strips (RR -2) NONE PROVIDED Total Contributing Impervious Acres for Sheetflow to Riparian Buffers/Filter Strips (RR -2) NONE PROVIDED https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 8/12 4/12/2019 NYSDEC eBusiness Portal System - View Submission Total Contributing Acres for Tree Planting/Tree Pit (RR -3) NONE PROVIDED Total Contributing Impervious Acres for Tree Planting/Tree Pit (RR -3) NONE PROVIDED Total Contributing Acres for Disconnection of Rooftop Runoff (RR -4) NONE PROVIDED RR Techniques (Volume Reduction) Total Contributing Impervious Acres for Disconnection of Rooftop Runoff (RR -4) NONE PROVIDED Total Contributing Impervious Acres for Vegetated Swale (RR -5) NONE PROVIDED Total Contributing Impervious Acres for Rain Garden (RR -6) NONE PROVIDED Total Contributing Impervious Acres for Stormwater Planter (RR -7) NONE PROVIDED Total Contributing Impervious Acres for Rain Barrel/Cistern (RR -8) NONE PROVIDED Total Contributing Impervious Acres for Porous Pavement (RR -9) NONE PROVIDED Total Contributing Impervious Acres for Green Roof (RR -10) NONE PROVIDED Standard SMPs with RRv Capacity Total Contributing Impervious Acres for Infiltration Trench (1-1) NONE PROVIDED Total Contributing Impervious Acres for Infiltration Basin (1-2) NONE PROVIDED Total Contributing Impervious Acres for Dry Well (1-3) NONE PROVIDED Total Contributing Impervious Acres for Underground Infiltration System (1-4) NONE PROVIDED Total Contributing Impervious Acres for Bioretention (F-5) 0.2 Total Contributing Impervious Acres for Dry Swale (0-1) NONE PROVIDED Standard SMPs Total Contributing Impervious Acres for Micropool Extended Detention (P-1) NONE PROVIDED Total Contributing Impervious Acres for Wet Pond (P-2) https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 9/12 4/12/2019 0.4 NYSDEC eBusiness Portal System - View Submission Total Contributing Impervious Acres for Wet Extended Detention (P-3) NONE PROVIDED Total Contributing Impervious Acres for Multiple Pond System (P-4) NONE PROVIDED Total Contributing Impervious Acres for Pocket Pond (P-5) NONE PROVIDED Total Contributing Impervious Acres for Surface Sand Filter (F-1) NONE PROVIDED Total Contributing Impervious Acres for Underground Sand Filter (F-2) NONE PROVIDED Total Contributing Impervious Acres for Perimeter Sand Filter (F-3) NONE PROVIDED Total Contributing Impervious Acres for Organic Filter (F-4) NONE PROVIDED Total Contributing Impervious Acres for Shallow Wetland (W-1) NONE PROVIDED Total Contributing Impervious Acres for Extended Detention Wetland (W-2) NONE PROVIDED Total Contributing Impervious Acres for Pond/Wetland System (W-3) NONE PROVIDED Total Contributing Impervious Acres for Pocket Wetland (W-4) NONE PROVIDED Total Contributing Impervious Acres for Wet Swale (0-2) NONE PROVIDED Alternative SMPs (DO NOT INCLUDE PRACTICES BEING USED FOR PRETREATMENT ONLY) Total Contributing Impervious Area for Hydrodynamic NONE PROVIDED Total Contributing Impervious Area for Wet Vault NONE PROVIDED Total Contributing Impervious Area for Media Filter NONE PROVIDED "Other" Alternative SMP? NONE PROVIDED Total Contributing Impervious Area for "Other" NONE PROVIDED Provide the name and manufaturer of the alternative SMPs (i.e. proprietary practice(s)) being used for WQv treatment. Note: Redevelopment projects which do not use RR techniques, shall use questions 28, 29, 33 and 33a to provide SMPs used, total WQv required and total WQv provided for the project. Manufacturer of Alternative SMP https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 10/12 4/12/2019 NYSDEC eBusiness Portal System - View Submission NONE PROVIDED Name of Alternative SMP NONE PROVIDED Other Permits 40. Identify other DEC permits, existing and new, that are required for this project/facility. None If SPDES Multi -Sector GP, then give permit ID NONE PROVIDED If Other, then identify NONE PROVIDED 41. Does this project require a US Army Corps of Engineers Wetland Permit? No If "Yes," then indicate Size of Impact, in acres, to the nearest tenth NONE PROVIDED 42. If this NOI is being submitted for the purpose of continuing or transferring coverage under a general permit for stormwater runoff from construction activities, please indicate the former SPDES number assigned. NONE PROVIDED MS4 SWPPP Acceptance 43. Is this project subject to the requirements of a regulated, traditional land use control MS4? Yes - Please attach the MS4 Acceptance form below If No, skip question 44 44. Has the "MS4 SWPPP Acceptance" form been signed by the principal executive officer or ranking elected official and submitted along with this NOI? Yes MS4 SWPPP Acceptance Form Download Download form from the link below. Complete, sign, and upload. MS4 SWPPP Acceptance Form MS4 Acceptance Form Upload - Attachment NONE PROVIDED Comment: NONE PROVIDED Owner/Operator Certification Owner/Operator Certification Form Download Download the certification form by clicking the link below. Complete, sign, scan, and upload the form. Owner/Operator Certification Form (PDF, 45KB) Upload Owner/Operator Certification Form * - Attachment NONE PROVIDED Comment: NONE PROVIDED https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 11/12 4/12/2019 NYSDEC eBusiness Portal System - View Submission Attachments Date Attachment Name Context Status History Date User Processing Status None Processing Steps Step Name Assigned To/Completed By Form Submitted Kara Tedford Deemed Complete Toni Cioffi Date Completed https:Hnform-prod.dec.ny.gov/SubmissionVersion/a7caceab-d377-426f-8c26-e5545dOda64a 12/12 New York State Department of Environmental Conservation Division of Water oboe625 Broadway, 4th Floor 'MR111111110V F,Albany, New York 12233-3505 MS4 Stormwater Pollution Prevention Plan (SWPPP) Acceptance Form for Construction Activities Seeking Authorization Under SPDES General Permit *(NOTE: Attach Completed Form to Notice Of Intent and Submit to Address Above) I. Project Owner/Operator Information 1. Owner/Operator Name: Skidmore College 2. Contact Person: Dan Rod e cke r 3. Street Address: 815 North Broadway 4. City/State/Zip: Saratoga Springs, NY 12866 II. Project Site Information 5. Project/Site Name: Skidmore Flex Building 6. Street Address: 815 North Broadway 7. City/State/Zip: Saratoga Springs, NY 12866 III. Stormwater Pollution Prevention Plan (SWPPP) Review and Acceptance Information 8. SWPPP Reviewed by: Timothy W. Wales 9. Title/Position: City Engineer 10. Date Final SWPPP Reviewed and Accepted: IV. Regulated MS4 Information 11. Name of MS4: City of Saratoga Springs 12. MS4 SPDES Permit Identification Number: NYR20A 216 13. Contact Person: Al Flick 14. Street Address: City Hall, 474 Broadway 15. City/State/Zip: Saratoga Springs, NY 12866 16. Telephone Number: 518-587-3550 (NYS DEC - MS4 SWPPP Acceptance Form - January 2010) Page 1 of 2 MS4 SWPPP Acceptance Form - continued V. Certification Statement - MS4 Official (principal executive officer or ranking elected official) or Duly Authorized Representative I hereby certify that the final Stormwater Pollution Prevention Plan (SWPPP) for the construction project identified in question 5 has been reviewed and meets the substantive requirements in the SPDES General Permit For Stormwater Discharges from Municipal Separate Storm Sewer Systems (MS4s). Note: The MS4, through the acceptance of the SWPPP, assumes no responsibility for the accuracy and adequacy of the design included in the SWPPP. In addition, review and acceptance of the SWPPP by the MS4 does not relieve the owner/operator or their SWPPP preparer of responsibility or liability for errors or omissions in the plan. Printed Name: Timothy Wales Title/Position: Civil Engineer / Stormwater Management Official Signature: Date: VI. Additional Information Page 2 of 2 Appendix B Stormwater Management Report Hydro CAD tcorm)m 40 Long Alley 518-587-8100 The LA GROUP Saratoga Springs 513-58-e-0180 La ted scape Architect u re & E ng -I neering P. C. NY 12866 www.thelagroup-com ormwater Management Report for: Skidmore College Swing Building 815 North Broadway Saratoga Springs, NY 12866 Owner/Operator(s): Skidmore College 815 North Broadway Saratoga Springs, NY 12866 SWM Report Contact(s): The LA Group, PC 40 Long Alley Saratoga Springs, NY 12866 1-518-587-8100 Project No. 201258 Preparation Date: 4/12/2019 Stormwater Management Report Table of Contents Contents Skidmore College Swing Building 2018135 1.0 INTRODUCTION .............................................................................................................................................. 4 2.0 PROJECT DESCRIPTION..............................................................................................................................4 2.1 SITE LOCATION................................................................................................................................................4 2.2 PROJECT DESCRIPTION.....................................................................................................................................4 2.3 SOIL CONDITIONS/SOIL TESTING.....................................................................................................................4 2.4 CURVE NUMBERS AND RAINFALL DATA.......................................................................................................... 5 3.0 EXISTING CONDITIONS...............................................................................................................................5 4.0 PROPOSED CONDITIONS.............................................................................................................................6 5.0 NYSDEC DESIGN CRITERIA........................................................................................................................6 5.1 SITE PLANNING TO PRESERVE NATURAL FEATURES........................................................................................7 5.2 WATER QUALITY VOLUME (WQV).................................................................................................................. 8 5.3 RUNOFF REDUCTION VOLUME (RRV).............................................................................................................. 9 5.4 CHANNEL PROTECTION VOLUME (CPV)........................................................................................................1 0 5.5 OVERBANK FLOOD (QP) AND EXTREME FLOOD (QF) ATTENUATION.............................................................1 0 6.0 PROPOSED STORMWATER FACILITIES...............................................................................................11 6.1 PRETREATMENT.............................................................................................................................................11 6.2 TREATMENT...................................................................................................................................................11 7.0 POST -CONSTRUCTION MAINTENANCE REQUIREMENTS..............................................................12 8.0 REFERENCES.................................................................................................................................................12 Stormwater Management Report Attachment A Soil Investigations Soil Survey Natural Resource Map Skidmore College Swing Building 2018135 B Existing Conditions Watershed Map and HydroCAD Calculations C Proposed Conditions Watershed Map and HydroCAD Calculations D Storm Data Stormwater Management Report Skidmore College Swing Building 2018135 1.0 INTRODUCTION The following is a Stormwater Management Report (SWM Report) developed for the Operator, Skidmore College, for the Skidmore Science Center Project, herein referred to as the "Project." It is prepared in accordance with the New York State Department of Environmental Conservation (NYSDEC) Stormwater Management Design Manual (SWMDM), dated January, 2015. The Project has been designed in accordance with Chapter 4 of the NYSDEC SWMDM and NYSDEC's General Permit GP -0-15-002 for construction activities. All new impervious area was designed in accordance with Chapter 4 of the SWMDM. The Project Site represents the area that will be disturbed as a result of the Project. Stormwater calculations were performed utilizing widely accepted engineering methodologies, including TR -55, and the stormwater modeling computer program HydroCAD (version 10.00) produced by HydroCAD Software Solutions, LLC. 2.0 PROJECT DESCRIPTION 2.1 Site Location The Project is located on North Broadway in the City of Saratoga Springs, Saratoga County, NY 12866. Access to the site is off of North Broadway, approximately 530 feet north of the intersection of 4th Street and North Broadway. 2.2 Project Description The intent of the Project is to construct a multiuse building in the northeast corner of the Skidmore College campus. This includes selective clearing and grubbing of an area east of the North Woods parking lot, construction of the Swing Building, construction of a fire access road and new paths, and expansion of the existing stormwater wet pond. The site developments described herein will results in a net increase in impervious area within the Proj ect's watershed. The project is considered new development per Chapters 4 of the SWMDM. All new impervious area was designed in accordance with Chapter 4 of the SWMDM. The Project Site represents the area that will be disturbed as a result of the Project. 2.3 Soil Conditions/Soil Testing According to the Natural Resources Conservation Service (NRCS) Soil Survey, the project site area is comprised of Farmington and Galway soil types. The hydrological soil group (HSG) classification for these soil types is D and C, respectively. LO The LA G L,Md sCap& Are h i i i: t • :, Engineering FC- 4 Stormwater Management Report 2.4 Curve Numbers and Rainfall Data Skidmore College Swing Building 2018135 The surface cover for the project area is primarily grassed areas, forest, existing parking and paths, and existing stormwater features. The curve numbers utilized in the modeling were assigned based on cover type and HSG soil classification. The design storms used for the pre -development versus post -development comparison were the 11 10, and 100 -year, 24-hour duration, SCS Type II events. The rainfall amounts for these storms are 2.15, 3.75, and 6.20 inches, respectively. 3.0 EXISTING CONDITIONS The Project area's existing condition, for which this stormwater management plan is based, consists of parking lots, a gravel path, forest, lawns, and existing stormwater features. Under the watershed's Existing Condition, the watershed is divided into 31 subcatchments, which generally flows to 1 analysis point. Runoff from the main project area is conveyed via a closed drainage network on the Skidmore College Campus to an existing stormwater pond that is located west of North Broadway. The HydroCAD model includes all campus areas that are conveyed to the stormwater pond in order to more accurately model site hydrology and hydraulics. The ma j ority of these areas are not a part of the project (Analysis Point 1). Two projects have occurred on campus in recent years which provided the basis for development of the campus stormwater model. The Palamountain Hall Building project was reviewed by the City of Saratoga Springs Planning Board and approved on 1/14/2016, with City approval of the site plans on 4/15/2016. The Skidmore College Center for Integrated Sciences project was reviewed by the City of Saratoga Springs Planning Board and approved 7/27/2017, with City approval of the site plans on 5/15/2018. There is an existing pond located near North Broadway, identified in the HydroCAD model as the Wet Pond. This pond has an outlet control structure that includes a 7 -inch by 6 -inch rectangular orifice at elevation 421.5, and a 24" by 24" grated frame on the top of the structure at elevation 424.0. The pond also has an overflow weir at elevation 424.0. Table 3-1 below provides a summary of the existing conditions peak discharge rates for the Project's watershed. Lc�i The LA G L,LeLd S. ap& Are h i i i: t • :, Engineering F C_ 5 Stormwater Management Report Skidmore College Swing Building 2018135 Table 3-1 Existing Conditions Peak Discharge Rates Analysis Point AP -1 Design Storm (cfs) 10 -Year 32.53 cfs 100 -Year 94.93 cfs Refer to Attachment B for more information on the existing conditions watershed modeling. 4.0 PROPOSED CONDITIONS Under the watershed's Proposed Condition, stormwater will continue to discharge to the North Broadway roadside ditch (AP -1). To meet NYSDEC requirements (see Section 5.0 NYSDEC Design Criteria of this report) the stormwater pond has been expanded and improved to accommodate an increase in stormwater runoff. A bioretention basin has been incorporated to manage stormwater treatment as well. Table 4-1 Existing Conditions vs. Proposed Conditions Peak Discharge Rates Analysis Point AP -1 Condition Existing Proposed Design Storm (cfs) (cfs) 10 -Year 32.53 26.63 100 -Year 94.93 94.26 Refer to Attachment C for more information on the proposed conditions watershed modeling. 5.0 NYSDEC DESIGN CRITERIA The NYSDEC SWMDM, dated January 2015 has been utilized to develop the stormwater management plan. The SWMDM includes a five-step process that involves site planning and stormwater management practice selection. The five steps include; • Site planning to preserve natural features and reduce impervious cover, • Calculation of the Water Quality Volume (WQv) for the Site, • Incorporation of green infrastructure techniques and standard SMPs with Runoff Reduction Volume (RRv) capacity, • Use of standard SMPs where applicable, to treat the portion of WQv not addressed by green infrastructure techniques and standard SMPs with RRv capacity, and LC 11 The LA G L,LeLd S. ap& Are h i i i: t • :, Engineering F C_ R Stormwater Management Report • Design of volume and peak rate control (where required) Skidmore College Swing Building 2018135 The approach of the stormwater management plan was to address the stormwater requirements separately. The five steps were reduced to Site Planning to Preserve Natural Features, Water Quality Volume, Runoff Reduction Volume, Channel Protection Volume, and Overbank Flood and Extreme Storm Attenuation, as discussed in the following sections. Attachment D of this report contains detailed calculations for determining and summarizing the required and provided volumes for Water Quality and Runoff Reduction. In general, the required design criteria (WQv and RRv) were calculated for all areas where site disturbance or green infrastructure techniques are proposed. 5.1 Site Planning to Preserve Natural Features Within Chapter 3 of the SWMDM, Table 3.1 Green Infrastructure Planning General Categories and Specific Practices includes a list of planning practices utilized in the planning and design of a project. There are two categories, Preservation of Natural Resources and Reduction of Impervious Cover. Preservation of Natural Resources includes: • Preservation of Undisturbed Areas • Preservation of Buffers • Reduction of Clearing and Grading • Locating Development in Less Sensitive Areas • Open Space Design • Soil Restoration Reduction of Impervious Cover includes: • Roadway Reduction • Sidewalk Reduction • Driveway Reduction • Cul-de-sac Reduction • Building Footprint Reduction • Parking Reduction A Natural Resource Map for Green Infrastructure Planning has been developed which indicates natural resource areas and critical environmental areas to be protected (where feasible). As required in Section 3.6 of the SWMDM, the map includes (where applicable): • Jurisdictional Wetlands o No jurisdictional wetlands are impacted by the Project. La The LA GROUP L,Md S. ap& Are h i i i: t • :, Engineering R. C_ 7 Stormwater Management Report Skidmore College Swing Building 2018135 • Waterways o No waterways are impacted by the Project. • Wetland Adjacent Area o There are no wetland areas adjacent to the Project. • Floodplains o The Project Site is not located within the 100 -year floodplain. • Forest, vegetative cover o The Project has been designed to minimize effects on forested areas. • Topography/Steep slopes o The Project Site does not include areas with steep slopes. • Existing soils, including hydrologic soil groups and soil erodibility o See Section 2.3 of this Report. • Drainage Patterns o See Section 3.0 of this Report. • Bedrock/Significant geological features o See Section 2.3 of this Report. The Natural Resource Plan indicates the areas to be avoided and depicts the area most suitable for development. 5.2 Water Quality Volume (WQv) The Water Quality Volume (WQv) requirement is designed to improve water quality sizing to capture and treat 90% of the average annual stormwater runoff volumes. The WQv is directly related to the amount of impervious cover created at a site. The following equation is used to determine the water quality storage volume. WQv = (P)(Rv)(A) 12 Where: WQv = Water quality volume (acre/feet) P = 90% Rainfall Event (1.15" for Saratoga Springs) Rv = 0.05 + 0.009(I) where I is percent impervious cover A = Site area in acres The required WQv will be treated via a bioretention basin (SMP -1) and the expanded wet pond (SMP -2), designed in accordance with the SWMDM. Refer to Table 5-1 for a summary of the required versus provided water quality volumes for the Project. LO The LA G L,LeLd S. ap& Are h i i i: t • :, Engineering R. C_ N6 Stormwater Management Report Skidmore College Swing Building 2018135 Table 5-1 Water Quality Volume WQv Summar SMP Type Required Provided (ac -ft) (ac -ft) SMP -1 Bioretention 0.02 0.02 SMP -2 Expanded Wet Pond 0.04 0.04 TOTAL 0.06 0.06 Refer to Attachment D for detailed WQv calculations. 5.3 Runoff Reduction Volume (RRv) Section 4.3 of the SWMDM states, "Runoff reduction shall be achieved by infiltration, groundwater recharge, reuse, recycle, evaporation/evapotranspiration of 100 percent of the post - development water quality volumes to replicate pre -development hydrology by maintaining pre - construction infiltration, peak runoff flow, discharge volume, as well as minimizing concentrated flow by using runoff control techniques to provide treatment in a distributed manner before runoff reaches the collection system." The stormwater management plan must demonstrate that all green infrastructure planning and design options were evaluated to meet the runoff reduction requirement. The following is a list of green infrastructure practices that were evaluated during design and specific limitations of the site: • 5.3.1 Conservation of Natural Areas o No conservation areas are proposed as part of this project due to lack of sufficient area on-site. • 5.3.2 Sheetflow to Riparian Buffers/Filter Strips o No filter strips are proposed as part of this project due to lack of sufficient area on-site. • 5.3.3 Vegetated Open Swales o Vegetated open swales are proposed as a part of this project for conveyance on the west side of the building. • 5.3.4 Tree Planting/Tree Box o Tree plantings are not proposed as a part of the project. • 5.3.5 Disconnection of Rooftop Runoff o Rooftop disconnection was not utilized as there is not sufficient receiving area. • 5.3.6 Stream Daylighting o All subsurface storm sewer piping will be daylighted as soon as possible. • 5.3.7 Rain Garden LO The LA G L,Md S. ap& Are h i i i: t • :, Engineering R. C_ I Stormwater Management Report Skidmore College Swing Building 2018135 o Rain gardens are typically applied for residential applications. The contributing drainage areas of project components exceed the maximum contributing area of 1,000 sf (for a rain garden), specified in the SWMDM. • 5.3.8 Green Roof o A green roof is not financially feasible for this project. • 5.3.9 Stormwater Planters o Stormwater planters have a limited contributing drainage area of 15,000 sf. Proposed roof exceeds the maximum contributing area. • 5.3. 10 Rain Tanks/Cisterns o Rain tanks/cisterns do not have any tangible functionality on this site as there is little potential for reuse. • 5.3.11 Porous Pavement o Porous pavement is not used as a part of the Proj ect due to shallow depth to groundwater. The RRv requirement on site is met through via a the bioretention. The bioretention will provide 0.02 ac -ft of RRv. This meets the minimum required RRv of 0.02 ac -ft. Refer to Attachment D for detailed RRv calculations. 5.4 Channel Protection Volume (CPv) Channel Protection Volume (CPv) is achieved by a volume reduction through green infrastructure practices, i.e. bioretention. The pre -development CPv was determined to be 46,984 cf, and the post -development CPv was determined to be 47,579 cf. The increase in CPv is therefore 595 cf, which will be managed onsite via volume reduction from the stormwater bioretention. The volume reduction from green infrastructure is 860 cf, which is greater than the required CPv of 595 cf. 5.5 Overbank Flood (Qp) and Extreme Flood (Qf) Attenuation The primary purpose of the Overbank Flood (Qp) control sizing criterion is to prevent an increase in the frequency and magnitude of out -of -bank flooding generated by urban development. It requires storage and attenuation of the 10 -year, 24-hour storm to ensure post - development peak discharge rates do not exceed the pre -development condition. The intent of the Extreme Flood (Qf) criteria is to (a) prevent the increased risk of flood damage from large storm events, (b) maintain the boundaries of the pre -development 100 -year floodplain, and (c) protect the physical integrity of stormwater management practices. It requires storage and attenuation of the 100 -year, 24-hour storm to ensure post -development peak discharge rates do not exceed the pre -development condition. LCI The [ A CROUP' . • ., . :, Engineering R.C_ 10 Stormwater Management Report Skidmore College Swing Building 2018135 During the 10 -year and 100 -year 24-hour storm the post -development peak discharge rates do not exceed the pre -development rates, as previously discussed. 6.0 PROPOSED STORMWATER FACILITIES The Project is proposing the expansion of the existing wet pond to address the stormwater requirements. To meet RRv requirements, a bioretention basin is proposed to be installed on site. The stormwater facilities have been indicated on the plans and HydroCAD reports as SMP -1 and SMP -2. A summary of the SMP is provided below. • SMP -1 is a bioretention basin north of the new Swing Building. • SMP -2 is a wet pond located east of the project area. This is an existing pond that will be expanded and improved to manage the increase in WQv. The Stormwater Facilities have been designed to provide the necessary pretreatment, treatment, and peak rate attenuation for stormwater runoff, for the project, as required by NYSDEC. 6.1 Pretreatment Pretreatment for the wet pond is provided via a hydrodynamic separator. Pretreatment for the bioretention is provided via a vegetated swale. 6.2 Treatment SMP -1 is a bioretention basin located north of the Swing Building. Stormwater will be treated here via infiltration through the bioretention soil mix. SMP -2 includes the expansion and improvement of an existing pond on site. The required expansion for the pond was based on the required WQv for the proposed work. The required WQv was calculated to be 0.06 ac -ft, determined by the acreage of disturbed existing impervious cover and new impervious cover. The bioretention basin is expected to provide 0.02 ac -ft in WQv treatment. The existing pond has an outlet control structure and an overflow weir, both of which are planned to be retained. The existing pond to be modified as a part of the proposed work currently has a permanent pool at elevation 421.5. The volume at the wet pond beneath the permanent pool elevation is currently 20,055 cf. The expansion of the pond will increase this permanent pool volume to 29,447 c£ The net increase in volume is therefore 9,392 cf, or 0.216 ac -ft. This is greater than the required WQv (0.06 ac -ft), so the pond improvements therefore meet the sizing requirements for WQv. The available pond free board during a 100 -year storm event was also maintained during resizing (1 foot). L() The LA GROUP L,Md S. ap& Are h i i i: t • :, Engineering R. C_ 11 Stormwater Management Report Skidmore College Swing Building 2018135 7.0 POST -CONSTRUCTION MAINTENANCE REQUIREMENTS Skidmore College will be responsible for the continuous upkeep and maintenance of all on-site stormwater management facilities. The on-site stormwater management facilities include SMP 1 and SMP 2. Maintenance includes, but is not limited to, removal of sediment from SMPs, cleaning conveyance channels of obstructions, and repairing any other detriments in the design that is resulting in the facilities to not function as intended in the design. 8.0 REFERENCES 1. Urban Hydrology for Small Watersheds. Published by the U.S. Soil Conservation Service, Washington, D.C., June 1986. 2. HydroCAD 10.00 Computer Program, by HydroCAD Software Solutions, LLC. 3. NYSDEC Stormwater Management Design Manual. Published by the New York State Department of Environmental Conservation, Updated January 2015. G:\Prof-2018\2018135_Skidmore_Flex_Building\2018135Enviro\02SWPPP\201258_SWM_Skidmore Science.doc LOM The LA G 12 Attachment A Soil Investigations Soil Survey Natural Resource Map USDA United States Department of - Agriculture N RCS Natural Resources Conservation Service A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Saratoga County, New York February 1, 2019 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http-//www.nres.usda.gov/wps/ portal/nres/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https-//offices.sc.egov.usda.gov/locator/app?agency=nres) or your NRCS State Soil Scientist (http-//www.nres.usda.gov/wps/portal/nres/detail/soils/contactus/? cid=nres142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 Contents Preface.................................................................................................................... 2 HowSoil Surveys Are Made..................................................................................5 SoilMap.................................................................................................................. 8 SoilMap................................................................................................................9 Legend................................................................................................................10 MapUnit Legend................................................................................................ 11 MapUnit Descriptions.........................................................................................11 SaratogaCounty, New York............................................................................13 FcC Farmington silt loam, 3 to 15 percent slopes, very rocky..................13 GaB Galway loam, 3 to 8 percent slopes ................................................. 14 References............................................................................................................16 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil -vegetation -landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 Custom Soil Resource Report scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components, the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil -landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil -landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field -observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and 0 Custom Soil Resource Report identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 0 Ln O 599100 430 6'6'N g 04 0 P N N 430 5'47" N 599100 599170 599240 599310 599380 io Ln Map Scale: 1:2,820 if printed on A portrait (8.5" x 11") sheet. 0 1111r- Meters N 0 40 80 160 240 Feet 0 100 200 400 600 Map projection: Web Mercator Comer coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 9 Custom Soil Resource Report Soil Map 599170 599240 599310 599380 ko O M 599520 430 6 6" N 0 04 o_ R ti N N 430 5'47" N 599520 io O O Q N ry N U L. O N ry O E O cn U O _ O LO O m L �� � U 0� O L) U) L U) m a) L N m cn N 0 O 0^ U (n L m U 'L O N E m O p L E E 9 m Z m aj Cm U c� ' a O � o 4 0 Ln m-0 " o �_ o M 0 0- " U) E L C Nm o N N O M��� > M L �. �Ma)�� o� o � -,.s C: �� W a (D E 0 o 0� � O 0- (. a) V � cn L�� �,�a) Z a IK - o �N N cn o E w� �o�> L o is Uw N cn 5 M M M o Z co O � N � ,� �� m am Q m 0 O 0 NEn E (n U N p 0 p� N � � }' o U � o� Q >' O o >+ > o m O O 0 m L m � U M }' O � •p � o (n O co m cn o o ui M� LL Z oC: cnm O i (6 0 M m O N cn (� • L E }' � O N Q� O U o U O N j �� � � 0)O M 'cn N (a M N 0 Cl) a O U >, m 0 m O � � � U O L L � J L U '� � � � ' C O �• (n � L N � � ) O � O L Q � - � O m O z E Q Q U O .--. C 0) O --� +r O i= �� O 0 0 0 ��.., is 0 L L O (� }N—, -0' O .� �_ O-0 � n > �+ L O O M: � O m Q i O (n is N (n N j O O U) (/) +r t6 O 4-0 U. o O +-� _ C L � 0 m DL cn 0 _cn O 1 M U U N � > o m O N _ O O Q O �70 m 1 O m m N .� L cn O N S cn >, U) > O O N O �+ N 0 '� C O U W U cn N o o- E 0 o 0 m O c v 0- m � O p (n (n p (nom M pj DN o c) cn � cn m m Li U m L- a ) m � cm o o mo n Q L O ma o L a0) �o _ Q O (n cn > Q) N F- O cn cn r_ m o m L- p Q) Q Z LL °a o L C7 m J a a = 00 p a)_ o L O CIL `-' j O 0-J �• O �� �• N En 4- E L:3 L cn Q) Q Q) O o c c6 C L }, a ca m Q❑ a >, o o — O m — � 0 (n Q OL U) a) +r C) a 2 — 2 2 LL o o — — U) >, � a) a) a) U) > > � � O � a) m � U m a) Q) L O Y a� U cn4-1 i Q 0 (n 0 0 = 0 O fn (n 'F) m m m U 0 L- � U CD CD c J J (1) 0- O (6 0� (n ca (1) w w w w O w c IL 0•� L � 'L) O ❑ El cn a Cl) O Custom Soil Resource Report Map Unit Legend Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, 11 Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI FcC Farmington silt loam, 3 to 15 percent slopes, very rocky 12.8 54.2% GaB Galway loam, 3 to 8 percent slopes 10.8 45.8% Totals for Area of Interest 23.5 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, 11 Custom Soil Resource Report onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha -Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha -Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. 12 Custom Soil Resource Report Saratoga County, New York FcC—Farmington silt loam, 3 to 15 percent slopes, very rocky Map Unit Setting National map unit symbol: 9w9z Elevation. 100 to 900 feet Mean annual precipitation. 36 to 48 inches Mean annual air temperature. 45 to 48 degrees F Frost -free period. 125 to 160 days Farmland classification: Not prime farmland Map Unit Composition Farmington, very rocky, and similar soils. 70 percent Minor components: 30 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Farmington, Very Rocky Setting Landform: Benches, ridges, till plains Landform position (two-dimensional). Shoulder Landform position (three-dimensional). Crest Down-slope shape. Convex Across -slope shape. Convex Parent material. Loamy till or congeliturbate derived from limestone, dolomite, shale, and sandstone, and in many places mixed with wind and water deposits Typical profile H1 - 0 to 9 inches. silt loam H2 - 9 to 15 inches: silt loam H3 - 15 to 25 inches. unweathered bedrock Properties and qualities Slope. 3 to 15 percent Depth to restrictive feature. 10 to 20 inches to lithic bedrock Natural drainage class. Well drained Capacity of the most limiting layer to transmit water (Ksat). Very low to high (0.00 to 1.98 in/hr) Depth to water table. More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 5 percent Available water storage in profile: Very low (about 2.1 inches) Interpretive groups Land capability classification (irrigated). None specified Land capability classification (nonirrigated): 6s Hydrologic Soil Group: D Hydric soil rating. No Minor Components Galway Percent of map unit. 10 percent Hydric soil rating. No 13 Custom Soil Resource Report Unnamed soils, moderately steep Percent of map unit. 8 percent Unnamed soils, very shallow Percent of map unit. 7 percent Rock outcrop Percent of map unit. 5 percent Hydric soil rating. Unranked GaB—Galway loam, 3 to 8 percent slopes Map Unit Setting National map unit symbol: 9wb1 Elevation. 150 to 1, 000 feet Mean annual precipitation. 36 to 48 inches Mean annual air temperature. 45 to 48 degrees F Frost -free period. 125 to 160 days Farmland classification: All areas are prime farmland Map Unit Composition Galway and similar soils. 65 percent Minor components: 35 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Galway Setting Landform: Benches, ridges, till plains Landform position (two-dimensional). Summit Landform position (three-dimensional). Crest Down-slope shape. Concave Across -slope shape. Convex Parent material. Calcareous loamy till Typical profile H1 - 0 to 6 inches. loam H2 - 6 to 28 inches: loam BC - 28 to 30 inches. fine sandy loam 2R - 30 to 40 inches. unweathered bedrock Properties and qualities Slope. 3 to 8 percent Depth to restrictive feature. 20 to 40 inches to lithic bedrock Natural drainage class. Moderately well drained Capacity of the most limiting layer to transmit water (Ksat). Very low to high (0.00 to 1.98 in/hr) Depth to water table. About 18 to 36 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 5 percent 14 Custom Soil Resource Report Available water storage in profile. Low (about 4.4 inches) Interpretive groups Land capability classification (irrigated). None specified Land capability classification (nonirrigated): 2e Hydrologic Soil Group: C Hydric soil rating. No Minor Components Charlton Percent of map unit. 15 percent Hydric soil rating. No Newstead Percent of map unit. 10 percent Hydric soil rating. No Farmington Percent of map unit. 10 percent Hydric soil rating. No 15 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep -water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http-//www.nres.usda.gov/wps/portal/ nres/detail/national/soils/?cid=nres142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www. nres. usda.gov/wps/portal/nres/detail/national/soils/?cid=nres142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11 th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www. nres. usda.gov/wps/portal/nres/detail/national/soils/?cid=nres142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http-//www.nres.usda.gov/wps/portal/nres/detail/soils/ home/?cid=nres142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http-//www.nres.usda.gov/wps/portal/nres/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 16 Custom Soil Resource Report United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 43041. http-//www.nres.usda.gov/wps/portal/ n res/deta i I/soi Is/scientists/?cid= n res 142 p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http-//www.nres.usda.gov/wps/portal/nres/detail/national/soils/? cid= n res 142 p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nres.usda.gov/Internet/FSE_DOCUMENTS/nresl42p2_052290.pdf 17 0 Jiao01 c � . o a 01. 4 Nhm N N N N 4 3 U l/i �° �w �aN oEy v�Zo ��zo zD LA DC rz s 12 Z � Z N C c a l./) min a V) Co to 6 zclf G 6 EL W Z 0 x 0 z obo//oj aaou,rpr; Attachment B Existing Conditions Watershed Map and HydroCAD Calculations Jia4 .0 11 cu 01. cu 0�8 0 D- > > 7 Ln 0 1 4- t t 0 12 [2 Z V) co 10 aballoj aa—Pms 0501103 010-\!-/5ObO1103 a,�OLUP!>ls JO SPUO/ JO "[)UD/ jo SPUO/ J/U U �sl PON I(Dmpvo-ja t/POA/ -------- lig 3 i < for � \� � `� � \ �-1—=� � � \�\ � � � \�� � � _ \� J�\ I I \ £ze — — — — — — — — — — — 4� OSG a� \ ISL \ /\ �— \ �\ \ \_�-�� \ �--� � _1_�M, / i � " �%�\ �' _ S T '3 00 51rN '0119 \ I / \ i� \ 6 _ — 6�4 j o��N�M � �� �\ � \\ �� \ �/ � �i ����� sL =— �J/ � �� � _J � \\�\ \�\� till �\ted JV r- A L6, IMT 1 0 -------------- 2n I 101J.oa "s K� 13 El \v L El I -------------------- - a �o a i� \\\X— Subcat Reach Aon Link OA13 Subcat 3 t 11 1.0 A26 Subcat 11 Existing Bioretention pie O Sutt 4 A36O2.0 O AO 10 pipe Existing B+oretention pipe Subcat 10 6 7 2.7 I I I I Sub at6 Sub at7 O Subc at2.7 Subcat 8 I O I � Subcat 9 c6 c6 D2 D6 CB CB CB ExCB11 2.5 YD2 YD6 YD6 to CB5 � 2 11 cBExz CB5 to O O xCB11 ExCB11 t E CB Subcat 2.5 O 2 19 Excei6 O O Aa Subcat 2.11 CBEjoCB5 3.0 OJ�� Subcat2.19 ExCB1BtExCB2B Subcat 2 CB7�YD2 2.10 12 Bioretention Subcat 2.6a CB 69C � ExC626 2.4c SF2 SF1 OSubcat 2.10 Subcat 12 Subcat 69C ExCB2B to CB13 Subcat 2.4cbcat SF2 Sub SH Subcat 5 ExcBia /201P SMP1 AP -1 CB13 ExCB1o CB13 CB to Ex ande et Pnd Foreba Wet Pond AP -1 \ 2.2 Subcat 2.2 2.1 2.4a 2.4b Subcat 2.1 Subcat 2.4a Subcat 2.4b ExCE6A 1.6 ExCB6Axpanded Subcat 1.6 We�tP nd c6 ExC63A 1.3 ExCB3 to 6A Subcat 1.3 \ c6 ExCB2A O(�� c6 ExCB5A CB ExCB2A f�ExCB3A Subcat 1.2 ExCB4A ExCBSAExCB4A ExCB4A ExCB3AExCB1A CB 1.5 1.4 ExCB1AExCB2A Subcat 1.5 Subcat 1.4 1.1 Subcat 1.1 Subcat Reach Aon Link Pre-Dev Skidmore Swing Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 5.343 74 >75% Grass cover, Good, HSG C (1.11 1.21 1.31 1.41 1.51 1.61 21 2.1) 2.101 2.111 2.191 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.7, 31 4, 51 61 7, 81 91 10, 11, 12, 69C, SF1, SF2) 0.528 80 >75% Grass cover, Good, HSG D (SF1, SF2) 8.947 98 Paved parking, HSG C (1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 212.11 2.10, 2.11, 2.191 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.7, 31 41 51 61 7) 81 91 101 11, 12, 69C, SF1, SF2) 0.011 98 Paved parking, HSG D (SF1) 7.416 70 Woods, Good, HSG C (2.19,2.4a, 2.4c, 4, 5, 9, 11, 69C, SF1, SF2) 2.804 77 Woods, Good, HSG D (SF1, SF2) 25.050 82 TOTAL AREA Pre-Dev Skidmore Swing Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 3 Soil Listing (all nodes) Area Soil Subcatchment (acres) Group Numbers 0.000 HSG A 0.000 HSG B 21.706 HSG C 1.11 1.21 1.31 1.41 1.51 1.61 21 2.11 2.101 2.111 2.191 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.71 31 41 51 61 71 8, 91 101 11, 121 69C, S F 1, S F2 3.344 HSG D SF1, SF2 0.000 Other 25.050 TOTAL AREA Pre-Dev Skidmore Swing Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 4 Ground Covers (all nodes) HSG -A HSG -B HSG -C HSG -D Other Total Ground Subcatchment (acres) (acres) (acres) (acres) (acres) (acres) Cover Numbers 0.000 0.000 5.343 0.528 0.000 0.000 0.000 8.947 0.011 0.000 5.871 >75% Grass cover, Good 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2)2.1) 2.10, 2.11, 2.19, 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.7, 3, 4, 5, 6, 7)8A 9, 10, 11, 12, 69C, SF1, SF2 8.958 Paved parking 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2)2.1) 2.10, 2.11, 2.19, 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.7, 3, 4, 5, 6, 7)8A 9, 10, 11, 12, 69C, SF1, SF2 0.000 0.000 7.416 2.804 0.000 10.220 Woods, Good 2.191 2.4a, 2.4c, 4, 5191 11, 69C, SF1, SF2 0.000 0.000 21.706 3.344 0.000 25.050 TOTAL AREA Pre-Dev Skidmore Swing Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 5 Pipe Listing (all nodes) Line# Node Number In -Invert (feet) Out -Invert (feet) Length (feet) Slope (ft/ft) n Diam/Width (inches) Height (inches) Inside -Fill (inches) 1 lop 470.00 468.00 50.0 0.0400 0.013 12.0 0.0 0.0 2 19P 465.00 462.00 155.0 0.0194 0.013 12.0 0.0 0.0 3 29P 461.00 457.00 90.0 0.0444 0.013 12.0 0.0 0.0 4 30P 456.50 455.40 220.0 0.0050 0.013 15.0 0.0 0.0 5 B3.0 445.45 444.95 75.0 0.0067 0.013 12.0 0.0 0.0 6 C B 13 430.76 422.90 234.0 0.0336 0.013 24.0 0.0 0.0 7 CB5 449.34 444.95 372.0 0.0118 0.013 18.0 0.0 0.0 8 CB7 456.00 455.40 114.0 0.0053 0.013 12.0 0.0 0.0 9 C B EX2 450.30 449.44 154.0 0.0056 0.013 12.0 0.0 0.0 10 ExCB11 444.90 439.90 280.0 0.0179 0.013 15.0 0.0 0.0 11 ExCB14 439.60 430.90 218.0 0.0399 0.013 15.0 0.0 0.0 12 ExCB1A 436.50 433.80 186.0 0.0145 0.013 12.0 0.0 0.0 13 ExCB1 B 457.15 449.76 130.0 0.0568 0.013 12.0 0.0 0.0 14 ExCB2A 433.70 431.40 186.0 0.0124 0.013 12.0 0.0 0.0 15 ExCB2B 449.50 431.24 392.0 0.0466 0.013 15.0 0.0 0.0 16 ExCB3A 431.30 426.67 50.0 0.0926 0.013 12.0 0.0 0.0 17 ExCB4A 433.35 431.40 73.0 0.0267 0.013 12.0 0.0 0.0 18 ExCB5A 436.80 433.35 133.0 0.0259 0.013 12.0 0.0 0.0 19 ExCB6A 426.67 424.51 80.0 0.0270 0.013 12.0 0.0 0.0 20 SMP 1 420.67 417.32 110.0 0.0305 0.013 8.0 0.0 0.0 21 YD2 455.30 452.21 176.0 0.0176 0.013 12.0 0.0 0.0 22 YD6 452.11 450.50 40.0 0.0403 0.013 12.0 0.0 0.0 Pre-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 6 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS, Weighted -CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1.1: Subcat 1.1 Runoff Area=0.275 ac 34.42% Impervious Runoff Depth>0.68" Flow Length=190' Tc=7.2 min CN=82 Runoff=0.34 cfs 0.016 of Subcatchment 1.2: Subcat 1.2 Runoff Area=0.268 ac 89.66% Impervious Runoff Depth>1.61" Tc=6.0 min CN=96 Runoff=0.74 cfs 0.036 of Subcatchment 1.3: Subcat 1.3 Runoff Area=0.384 ac 85.26% Impervious Runoff Depth>1.44" Tc=6.0 min CN=94 Runoff=0.97 cfs 0.046 of Subcatchment 1.4: Subcat 1.4 Runoff Area=0.554 ac 56.77% Impervious Runoff Depth>1.00" Tc=6.0 min CN=88 Runoff=1.04 cfs 0.046 of Subcatchment 1.5: Subcat 1.5 Runoff Area=0.128 ac 93.32% Impervious Runoff Depth>1.61" Tc=6.0 min CN=96 Runoff=0.35 cfs 0.017 of Subcatchment 1.6: Subcat 1.6 Runoff Area=0.182 ac 33.26% Impervious Runoff Depth>0.68" Tc=6.0 min CN=82 Runoff=0.24 cfs 0.010 of Subcatchment2: Subcat 2 Runoff Area=0.249 ac 71.95% Impervious Runoff Depth>1.20" Tc=6.0 min CN=91 Runoff=0.55 cfs 0.025 of Subcatchment2.1: Subcat 2.1 Runoff Area=0.428 ac 56.79% Impervious Runoff Depth>1.00" Tc=6.0 min CN=88 Runoff=0.80 cfs 0.036 of Subcatchment2.10: Subcat 2.10 Runoff Area=0.725 ac 99.80% Impervious Runoff Depth>1.79" Tc=6.0 min CN=98 Runoff=2.11 cfs 0.108 of Subcatchment2.11: Subcat 2.11 Runoff Area=0.087 ac 25.99% Impervious Runoff Depth>0.59" Tc=6.0 min CN=80 Runoff=0.10 cfs 0.004 of Subcatchment2.19: Subcat 2.19 Runoff Area=2.912 ac 29.59% Impervious Runoff Depth>0.54" Flow Length=369' Tc=22.4 min CN=79 Runoff=1.69 cfs 0.132 of Subcatchment2.2: Subcat 2.2 Runoff Area=0.882 ac 99.37% Impervious Runoff Depth>1.79" Tc=6.0 min CN=98 Runoff=2.57 cfs 0.132 of Subcatchment2.4a: Subcat 2.4a Runoff Area=2.326 ac 56.58% Impervious Runoff Depth>0.94" Flow Length=457' Tc=19.4 min CN=87 Runoff=2.67 cfs 0.181 of Subcatchment2.4b: Subcat 2.4b Runoff Area=0.199 ac 54.92% Impervious Runoff Depth>0.94" Tc=6.0 min CN=87 Runoff=0.35 cfs 0.016 of Subcatchment2.4c: Subcat 2.4c Runoff Area=0.505 ac 28.52% Impervious Runoff Depth>0.59" Flow Length=320' Tc=6.2 min CN=80 Runoff=0.56 cfs 0.025 of Subcatchment2.5: Subcat 2.5 Runoff Area=0.188 ac 41.66% Impervious Runoff Depth>0.78" Tc=6.0 min CN=84 Runoff=0.28 cfs 0.012 of Pre-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 7 Subcatchment2.6a: Subcat 2.6a Runoff Area=0.193 ac 38.35% Impervious Runoff Depth>0.73" Tc=6.0 min CN=83 Runoff=0.27 cfs 0.012 of Subcatchment2.7: Subcat 2.7 Runoff Area=0.274 ac 99.93% Impervious Runoff Depth>1.79" Tc=6.0 min CN=98 Runoff=0.80 cfs 0.041 of Subcatchmentl Subcat 3 Runoff Area=0.343 ac 85.99% Impervious Runoff Depth>1.52" Tc=6.0 min CN=95 Runoff=0.91 cfs 0.044 of Subcatchment4: Subcat 4 Runoff Area=1.290 ac 34.08% Impervious Runoff Depth>0.63" Flow Length=313' Tc=8.5 min CN=81 Runoff=1.43 cfs 0.068 of Subcatchment5: Subcat 5 Runoff Area=0.448 ac 27.63% Impervious Runoff Depth>0.59" Flow Length=249' Tc=11.8 min CN=80 Runoff=0.40 cfs 0.022 of Subcatchment6: Subcat 6 Runoff Area=0.241 ac 17.44% Impervious Runoff Depth>0.51" Tc=6.0 min CN=78 Runoff=0.23 cfs 0.010 of Subcatchment7: Subcat 7 Runoff Area=0.144 ac 4.83% Impervious Runoff Depth>0.40" Tc=6.0 min CN=75 Runoff=0.11 cfs 0.005 of Subcatchment8: Subcat 8 Runoff Area=0.151 ac 21.63% Impervious Runoff Depth>0.55" Flow Length=133' Tc=6.5 min CN=79 Runoff=0.16 cfs 0.007 of Subcatchment9: Subcat 9 Runoff Area=0.895 ac 53.57% Impervious Runoff Depth>0.94" Tc=6.0 min CN=87 Runoff=1.58 cfs 0.070 of Subcatchment 10: Subcat 10 Runoff Area=0.441 ac 83.28% Impervious Runoff Depth>1.44" Tc=6.0 min CN=94 Runoff=1.12 cfs 0.053 of Subcatchment 11: Subcat 11 Runoff Area=0.412 ac 29.82% Impervious Runoff Depth>0.59" Flow Length=187' Tc=7.1 min CN=80 Runoff=0.45 cfs 0.020 of Subcatchment 12: Subcat 12 Runoff Area=0.262 ac 54.24% Impervious Runoff Depth>0.94" Tc=6.0 min CN=87 Runoff=0.46 cfs 0.021 of Subcatchment69C: Subcat 69C Runoff Area=0.817 ac 25.59% Impervious Runoff Depth>0.51" Flow Length=509' Tc=17.4 min CN=78 Runoff=0.51 cfs 0.034 of SubcatchmentSF1: Subcat SH Runoff Area=6.439 ac 6.17% Impervious Runoff Depth>0.40" Flow Length=761' Tc=23.2 min CN=75 Runoff=2.46 cfs 0.214 of SubcatchmentSF2: Subcat SF2 Runoff Area=2.408 ac 10.02% Impervious Runoff Depth>0.43" Flow Length=570' Tc=22.7 min CN=76 Runoff=1.04 cfs 0.087 of Pond 10P: pipe Peak Elev=470.49' Inflow=0.91 cfs 0.044 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0400'/' Outflow=0.91 cfs 0.044 of Pond 19P: pipe Peak Elev=465.55' Inflow=1.12 cfs 0.053 of 12.0" Round Culvert n=0.013 L=155.0' S=0.0194'/' Outflow=1.12 cfs 0.053 of Pond 29P: pipe Peak Elev=461.32' Inflow=0.42 cfs 0.045 of 12.0" Round Culvert n=0.013 L=90.0' S=0.0444'/' Outflow=0.42 cfs 0.045 of Pre-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 8 Pond 30P: pipe Peak Elev=457.23' Inflow=1.75 cfs 0.139 of 15.0" Round Culvert n=0.013 L=220.0' S=0.0050'/' Outflow=1.75 cfs 0.139 of Pond 201 P: Forebay Peak Elev=423.58' Storage=0.136 of Inflow=16.90 cfs 1.169 of Outflow=15.56 cfs 1.154 of Pond B1.0: Existing Bioretention Peak Elev=465.85' Storage=0.027 of Inflow=1.34 cfs 0.064 of Outflow=0.42 cfs 0.045 of Pond B2.0: Existing Bioretention Peak EIev=460.47' Storage=0.041 of Inflow=2.49 cfs 0.121 of Primary=1.35 cfs 0.094 of Secondary=0.00 cfs 0.000 of Outflow=1.35 cfs 0.094 of Pond B3.0: Bioretention Peak EIev=447.70' Storage=0.009 of Inflow=0.27 cfs 0.012 of Outflow=0.01 cfs 0.003 of Pond CB13: CB13 to Expanded Wet Pond Peak Elev=432.53' Inflow=13.31 cfs 0.998 of 24.0" Round Culvert n=0.013 L=234.0' S=0.0336'/' Outflow=13.31 cfs 0.998 of Pond CB5: CB5 to ExCB11 Peak EIev=450.41' Inflow=4.78 cfs 0.243 of 18.0" Round Culvert n=0.013 L=372.0' S=0.0118 '/' Outflow=4.78 cfs 0.243 of Pond CB7: CB7 to YD2 Peak Elev=456.55' Inflow=0.88 cfs 0.047 of 12.0" Round Culvert n=0.013 L=114.0' S=0.0053'/' Outflow=0.88 cfs 0.047 of Pond CBEX2: CBEX2 to CB5 Peak Elev=451.31' Inflow=2.21 cfs 0.112 of 12.0" Round Culvert n=0.013 L=154.0' S=0.0056'/' Outflow=2.21 cfs 0.112 of Pond ExCB1 1: ExCB11 to ExCB14 Peak Elev=446.91' Inflow=6.96 cfs 0.467 of 15.0" Round Culvert n=0.013 L=280.0' S=0.0179'/' Outflow=6.96 cfs 0.467 of Pond ExCB1 4: ExCB14 to CB13 Peak Elev=442.78' Inflow=9.49 cfs 0.598 of 15.0" Round Culvert n=0.013 L=218.0' S=0.0399'/' Outflow=9.49 cfs 0.598 of Pond ExCB1 A: ExCB1 A to ExCB2A Peak Elev=436.79' Inflow=0.34 cfs 0.016 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0145'/' Outflow=0.34 cfs 0.016 of Pond ExCB1 B: ExCB1 B to ExCB2B Peak Elev=457.86' Inflow=1.69 cfs 0.132 of 12.0" Round Culvert n=0.013 L=130.0' S=0.0568'/' Outflow=1.69 cfs 0.132 of Pond ExCB2A: ExCB2A to ExCB3A Peak Elev=434.24' Inflow=1.06 cfs 0.052 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0124'/' Outflow=1.06 cfs 0.052 of Pond ExCB2B: ExCB2B to CB13 Peak EIev=450.23' Inflow=2.17 cfs 0.167 of 15.0" Round Culvert n=0.013 L=392.0' S=0.0466'/' Outflow=2.17 cfs 0.167 of Pond ExCB3A: ExCB3A to ExCB6A Peak Elev=432.61' Inflow=3.42 cfs 0.161 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0926'/' Outflow=3.42 cfs 0.161 of Pond ExCB4A: ExCB4A to ExCB3A Peak Elev=433.98' Inflow=1.39 cfs 0.064 of 12.0" Round Culvert n=0.013 L=73.0' S=0.0267'/' Outflow=1.39 cfs 0.064 of Pre-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 9 Pond ExCB5A: ExCB5A to ExCB4A Peak EIev=437.09' Inflow=0.35 cfs 0.017 of 12.0" Round Culvert n=0.013 L=133.0' S=0.0259'/' Outflow=0.35 cfs 0.017 of Pond ExCB6A: ExCB6A to Expanded Wet Pond Peak EIev=428.10' Inflow=3.65 cfs 0.171 of 12.0" Round Culvert n=0.013 L=80.0' S=0.0270 '/' Outflow=3.65 cfs 0.171 of Pond SMP1: Wet Pond Peak Elev=423.58' Storage=0.974 of Inflow=16.49 cfs 1.265 of Primary=1.90 cfs 1.111 of Secondary=0.00 cfs 0.000 of Outflow=1.90 cfs 1.111 of Pond YD2: YD2 to YD6 Peak Elev=455.85' Inflow=1.11 cfs 0.057 of 12.0" Round Culvert n=0.013 L=176.0' S=0.0176'/' Outflow=1.11 cfs 0.057 of Pond YD6: YD6 to CB5 Peak Elev=452.69' Inflow=1.22 cfs 0.062 of 12.0" Round Culvert n=0.013 L=40.0' S=0.0403'/' Outflow=1.22 cfs 0.062 of Link AP -1: AP -1 Inflow=4.18 cfs 1.325 of Primary=4.18 cfs 1.325 of Total Runoff Area = 25.050 ac Runoff Volume = 1.550 of Average Runoff Depth = 0.74" 64.24% Pervious = 16.091 ac 35.76% Impervious = 8.958 ac Pre-Dev Skidmore Swing Type 11 24 -hr 10 -year Rainfall=3.75" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 10 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS, Weighted -CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1.1: Subcat 1.1 Runoff Area=0.275 ac 34.42% Impervious Runoff Depth>1.84" Flow Length=190' Tc=7.2 min CN=82 Runoff=0.92 cfs 0.042 of Subcatchment 1.2: Subcat 1.2 Runoff Area=0.268 ac 89.66% Impervious Runoff Depth>3.07" Tc=6.0 min CN=96 Runoff=1.35 cfs 0.069 of Subcatchment 1.3: Subcat 1.3 Runoff Area=0.384 ac 85.26% Impervious Runoff Depth>2.89" Tc=6.0 min CN=94 Runoff=1.87 cfs 0.092 of Subcatchment 1.4: Subcat 1.4 Runoff Area=0.554 ac 56.77% Impervious Runoff Depth>2.33" Tc=6.0 min CN=88 Runoff=2.32 cfs 0.108 of Subcatchment 1.5: Subcat 1.5 Runoff Area=0.128 ac 93.32% Impervious Runoff Depth>3.07" Tc=6.0 min CN=96 Runoff=0.65 cfs 0.033 of Subcatchment 1.6: Subcat 1.6 Runoff Area=0.182 ac 33.26% Impervious Runoff Depth>1.84" Tc=6.0 min CN=82 Runoff=0.62 cfs 0.028 of Subcatchment2: Subcat 2 Runoff Area=0.249 ac 71.95% Impervious Runoff Depth>2.60" Tc=6.0 min CN=91 Runoff=1.13 cfs 0.054 of S u bcatch me nt 2.1: Subcat 2.1 Runoff Area=0.428 ac 56.79% Impervious Runoff Depth>2.33" Tc=6.0 min CN=88 Runoff=1.79 cfs 0.083 of Subcatchment2.10: Subcat 2.10 Runoff Area=0.725 ac 99.80% Impervious Runoff Depth>3.24" Tc=6.0 min CN=98 Runoff=3.75 cfs 0.196 of Subcatchment2.11: Subcat 2.11 Runoff Area=0.087 ac 25.99% Impervious Runoff Depth>1.69" Tc=6.0 min CN=80 Runoff=0.27 cfs 0.012 of Subcatchment2.19: Subcat 2.19 Runoff Area=2.912 ac 29.59% Impervious Runoff Depth>1.61" Flow Length=369' Tc=22.4 min CN=79 Runoff=5.29 cfs 0.390 of Subcatchment2.2: Subcat 2.2 Runoff Area=0.882 ac 99.37% Impervious Runoff Depth>3.24" Tc=6.0 min CN=98 Runoff=4.56 cfs 0.238 of Subcatchment2.4a: Subcat 2.4a Runoff Area=2.326 ac 56.58% Impervious Runoff Depth>2.23" Flow Length=457' Tc=19.4 min CN=87 Runoff=6.28 cfs 0.433 of Subcatchment2.4b: Subcat 2.4b Runoff Area=0.199 ac 54.92% Impervious Runoff Depth>2.24" Tc=6.0 min CN=87 Runoff=0.81 cfs 0.037 of Subcatchment2.4c: Subcat 2.4c Runoff Area=0.505 ac 28.52% Impervious Runoff Depth>1.69" Flow Length=320' Tc=6.2 min CN=80 Runoff=1.60 cfs 0.071 of Subcatchment2.5: Subcat 2.5 Runoff Area=0.188 ac 41.66% Impervious Runoff Depth>1.99" Tc=6.0 min CN=84 Runoff=0.69 cfs 0.031 of Pre-Dev Skidmore Swing Type 11 24 -hr 10 -year Rainfall=3.75" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 11 Subcatchment2.6a: Subcat 2.6a Runoff Area=0.193 ac 38.35% Impervious Runoff Depth>1.91" Tc=6.0 min CN=83 Runoff=0.69 cfs 0.031 of Subcatchment2.7: Subcat 2.7 Runoff Area=0.274 ac 99.93% Impervious Runoff Depth>3.24" Tc=6.0 min CN=98 Runoff=1.42 cfs 0.074 of Subcatchmentl Subcat 3 Runoff Area=0.343 ac 85.99% Impervious Runoff Depth>2.98" Tc=6.0 min CN=95 Runoff=1.70 cfs 0.085 of Subcatchment4: Subcat 4 Runoff Area=1.290 ac 34.08% Impervious Runoff Depth>1.76" Flow Length=313' Tc=8.5 min CN=81 Runoff=3.96 cfs 0.189 of Subcatchment5: Subcat 5 Runoff Area=0.448 ac 27.63% Impervious Runoff Depth>1.69" Flow Length=249' Tc=11.8 min CN=80 Runoff=1.18 cfs 0.063 of Subcatchment6: Subcat 6 Runoff Area=0.241 ac 17.44% Impervious Runoff Depth>1.55" Tc=6.0 min CN=78 Runoff=0.70 cfs 0.031 of Subcatchment7: Subcat 7 Runoff Area=0.144 ac 4.83% Impervious Runoff Depth>1.35" Tc=6.0 min CN=75 Runoff=0.37 cfs 0.016 of Subcatchment8: Subcat 8 Runoff Area=0.151 ac 21.63% Impervious Runoff Depth>1.62" Flow Length=133' Tc=6.5 min CN=79 Runoff=0.46 cfs 0.020 of Subcatchment9: Subcat 9 Runoff Area=0.895 ac 53.57% Impervious Runoff Depth>2.24" Tc=6.0 min CN=87 Runoff=3.63 cfs 0.167 of Subcatchment 10: Subcat 10 Runoff Area=0.441 ac 83.28% Impervious Runoff Depth>2.89" Tc=6.0 min CN=94 Runoff=2.15 cfs 0.106 of Subcatchment 11: Subcat 11 Runoff Area=0.412 ac 29.82% Impervious Runoff Depth>1.69" Flow Length=187' Tc=7.1 min CN=80 Runoff=1.28 cfs 0.058 of Subcatchment 12: Subcat 12 Runoff Area=0.262 ac 54.24% Impervious Runoff Depth>2.24" Tc=6.0 min CN=87 Runoff=1.06 cfs 0.049 of Subcatchment69C: Subcat 69C Runoff Area=0.817 ac 25.59% Impervious Runoff Depth>1.54" Flow Length=509' Tc=17.4 min CN=78 Runoff=1.64 cfs 0.105 of SubcatchmentSF1: Subcat SH Runoff Area=6.439 ac 6.17% Impervious Runoff Depth>1.34" Flow Length=761' Tc=23.2 min CN=75 Runoff=9.44 cfs 0.719 of SubcatchmentSF2: Subcat SF2 Runoff Area=2.408 ac 10.02% Impervious Runoff Depth>1.40" Flow Length=570' Tc=22.7 min CN=76 Runoff=3.77 cfs 0.282 of Pond 10P: pipe Peak EIev=470.71' Inflow=1.70 cfs 0.085 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0400'/' Outflow=1.70 cfs 0.085 of Pond 19P: pipe Peak Elev=493.49' Inflow=2.15 cfs 0.106 of 12.0" Round Culvert n=0.013 L=155.0' S=0.0194'/' Outflow=2.15 cfs 0.106 of Pond 29P: pipe Peak EIev=502.06' Inflow=3.25 cfs 0.120 of 12.0" Round Culvert n=0.013 L=90.0' S=0.0444'/' Outflow=3.25 cfs 0.120 of Pre-Dev Skidmore Swing Type 11 24 -hr 10 -year Rainfall=3.75" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 12 Pond 30P: pipe Peak EIev=502.07' Inflow=8.42 cfs 0.353 of 15.0" Round Culvert n=0.013 L=220.0' S=0.0050'/' Outflow=8.42 cfs 0.353 of Pond 201 P: Forebay Peak Elev=424.64' Storage=0.219 of Inflow=41.69 cfs 2.780 of Outflow=35.63 cfs 2.711 of Pond B1.0: Existing Bioretention Peak Elev=466.27' Storage=0.044 of Inflow=2.93 cfs 0.143 of Outflow=3.25 cfs 0.120 of Pond B2.0: Existing Bioretention Peak Elev=493.46' Storage=0.081 of Inflow=6.01 cfs 0.295 of Primary=5.91 cfs 0.233 of Secondary=3.74 cfs 0.033 of Outflow=5.94 cfs 0.266 of Pond B3.0: Bioretention Peak EIev=448.05' Storage=0.017 of Inflow=0.69 cfs 0.031 of Outflow=1.39 cfs 0.022 of Pond CB13: CB13 to Expanded Wet Pond Peak Elev=436.63' Inflow=33.37 cfs 2.409 of 24.0" Round Culvert n=0.013 L=234.0' S=0.0336'/' Outflow=33.37 cfs 2.409 of Pond CB5: CB5 to ExCB11 Peak EIev=499.05' Inflow=10.07 cfs 0.516 of 18.0" Round Culvert n=0.013 L=372.0' S=0.0118'/' Outflow= 10.07 cfs 0.516 of Pond CB7: CB7 to YD2 Peak EIev=499.50' Inflow=2.16 cfs 0.117 of 12.0" Round Culvert n=0.013 L=114.0' S=0.0053'/' Outflow=2.16 cfs 0.117 of Pond CBEX2: CBEX2 to CB5 Peak Elev=499.27' Inflow=4.02 cfs 0.208 of 12.0" Round Culvert n=0.013 L=154.0' S=0.0056'/' Outflow=4.02 cfs 0.208 of Pond ExCB1 1: ExCB11 to ExCB14 Peak Elev=497.33' Inflow=19.92 cfs 1.122 of 15.0" Round Culvert n=0.013 L=280.0' S=0.0179'/' Outflow=19.92 cfs 1.122 of Pond ExCB1 4: ExCB14 to CB13 Peak Elev=475.29' Inflow=24.47 cfs 1.360 of 15.0" Round Culvert n=0.013 L=218.0' S=0.0399'/' Outflow=24.47 cfs 1.360 of Pond ExCB1 A: ExCB1 A to ExCB2A Peak EIev=437.01' Inflow=0.92 cfs 0.042 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0145'/' Outflow=0.92 cfs 0.042 of Pond ExCB1 B: ExCB1 B to ExCB2B Peak Elev=459.61' Inflow=5.29 cfs 0.390 of 12.0" Round Culvert n=0.013 L=130.0' S=0.0568'/' Outflow=5.29 cfs 0.390 of Pond ExCB2A: ExCB2A to ExCB3A Peak EIev=436.06' Inflow=2.24 cfs 0.111 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0124'/' Outflow=2.24 cfs 0.111 of Pond ExCB2B: ExCB2B to CB13 Peak Elev=451.46' Inflow=6.82 cfs 0.495 of 15.0" Round Culvert n=0.013 L=392.0' S=0.0466'/' Outflow=6.82 cfs 0.495 of Pond ExCB3A: ExCB3A to ExCB6A Peak Elev=435.27' Inflow=7.06 cfs 0.344 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0926'/' Outflow=7.06 cfs 0.344 of Pond ExCB4A: ExCB4A to ExCB3A Peak Elev=435.94' Inflow=2.97 cfs 0.140 of 12.0" Round Culvert n=0.013 L=73.0' S=0.0267'/' Outflow=2.97 cfs 0.140 of Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 1 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS, Weighted -CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1.1: Subcat 1.1 Runoff Area=0.275 ac 34.42% Impervious Runoff Depth>3.89" Flow Length=190' Tc=7.2 min CN=82 Runoff=1.87 cfs 0.089 of Subcatchment 1.2: Subcat 1.2 Runoff Area=0.268 ac 89.66% Impervious Runoff Depth>5.30" Tc=6.0 min CN=96 Runoff=2.29 cfs 0.119 of Subcatchment 1.3: Subcat 1.3 Runoff Area=0.384 ac 85.26% Impervious Runoff Depth>5.12" Tc=6.0 min CN=94 Runoff=3.21 cfs 0.164 of Subcatchment 1.4: Subcat 1.4 Runoff Area=0.554 ac 56.77% Impervious Runoff Depth>4.52" Tc=6.0 min CN=88 Runoff=4.31 cfs 0.209 of Subcatchment 1.5: Subcat 1.5 Runoff Area=0.128 ac 93.32% Impervious Runoff Depth>5.30" Tc=6.0 min CN=96 Runoff=1.09 cfs 0.057 of Subcatchment 1.6: Subcat 1.6 Runoff Area=0.182 ac 33.26% Impervious Runoff Depth>3.89" Tc=6.0 min CN=82 Runoff=1.27 cfs 0.059 of Subcatchment2: Subcat 2 Runoff Area=0.249 ac 71.95% Impervious Runoff Depth>4.83" Tc=6.0 min CN=91 Runoff=2.02 cfs 0.100 of Subcatchment2.1: Subcat 2.1 Runoff Area=0.428 ac 56.79% Impervious Runoff Depth>4.52" Tc=6.0 min CN=88 Runoff=3.33 cfs 0.161 of Subcatchment2.10: Subcat 2.10 Runoff Area=0.725 ac 99.80% Impervious Runoff Depth>5.45" Tc=6.0 min CN=98 Runoff=6.23 cfs 0.329 of Subcatchment2.11: Subcat 2.11 Runoff Area=0.087 ac 25.99% Impervious Runoff Depth>3.69" Tc=6.0 min CN=80 Runoff=0.58 cfs 0.027 of Subcatchment2.19: Subcat 2.19 Runoff Area=2.912 ac 29.59% Impervious Runoff Depth>3.57" Flow Length=369' Tc=22.4 min CN=79 Runoff=11.64 cfs 0.866 of Subcatchment2.2: Subcat 2.2 Runoff Area=0.882 ac 99.37% Impervious Runoff Depth>5.45" Tc=6.0 min CN=98 Runoff=7.59 cfs 0.401 of Subcatchment2.4a: Subcat 2.4a Runoff Area=2.326 ac 56.58% Impervious Runoff Depth>4.40" Flow Length=457' Tc=19.4 min CN=87 Runoff=11.99 cfs 0.853 of Subcatchment2.4b: Subcat 2.4b Runoff Area=0.199 ac 54.92% Impervious Runoff Depth>4.41" Tc=6.0 min CN=87 Runoff=1.52 cfs 0.073 of Subcatchment2.4c: Subcat 2.4c Runoff Area=0.505 ac 28.52% Impervious Runoff Depth>3.69" Flow Length=320' Tc=6.2 min CN=80 Runoff=3.34 cfs 0.155 of Subcatchment2.5: Subcat 2.5 Runoff Area=0.188 ac 41.66% Impervious Runoff Depth>4.10" Tc=6.0 min CN=84 Runoff=1.36 cfs 0.064 of Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 2 Subcatchment2.6a: Subcat 2.6a Runoff Area=0.193 ac 38.35% Impervious Runoff Depth>4.00" Tc=6.0 min CN=83 Runoff=1.38 cfs 0.064 of Subcatchment2.7: Subcat 2.7 Runoff Area=0.274 ac 99.93% Impervious Runoff Depth>5.45" Tc=6.0 min CN=98 Runoff=2.36 cfs 0.125 of Subcatchmentl Subcat 3 Runoff Area=0.343 ac 85.99% Impervious Runoff Depth>5.22" Tc=6.0 min CN=95 Runoff=2.89 cfs 0.149 of Subcatchment4: Subcat 4 Runoff Area=1.290 ac 34.08% Impervious Runoff Depth>3.79" Flow Length=313' Tc=8.5 min CN=81 Runoff=8.25 cfs 0.407 of Subcatchment5: Subcat 5 Runoff Area=0.448 ac 27.63% Impervious Runoff Depth>3.68" Flow Length=249' Tc=11.8 min CN=80 Runoff=2.50 cfs 0.137 of Subcatchment6: Subcat 6 Runoff Area=0.241 ac 17.44% Impervious Runoff Depth>3.49" Tc=6.0 min CN=78 Runoff=1.53 cfs 0.070 of Subcatchment7: Subcat 7 Runoff Area=0.144 ac 4.83% Impervious Runoff Depth>3.19" Tc=6.0 min CN=75 Runoff=0.85 cfs 0.038 of Subcatchment8: Subcat 8 Runoff Area=0.151 ac 21.63% Impervious Runoff Depth>3.59" Flow Length=133' Tc=6.5 min CN=79 Runoff=0.98 cfs 0.045 of Subcatchment9: Subcat 9 Runoff Area=0.895 ac 53.57% Impervious Runoff Depth>4.41" Tc=6.0 min CN=87 Runoff=6.85 cfs 0.329 of Subcatchment 10: Subcat 10 Runoff Area=0.441 ac 83.28% Impervious Runoff Depth>5.12" Tc=6.0 min CN=94 Runoff=3.69 cfs 0.188 of Subcatchment 11: Subcat 11 Runoff Area=0.412 ac 29.82% Impervious Runoff Depth>3.69" Flow Length=187' Tc=7.1 min CN=80 Runoff=2.69 cfs 0.127 of Subcatchment 12: Subcat 12 Runoff Area=0.262 ac 54.24% Impervious Runoff Depth>4.41" Tc=6.0 min CN=87 Runoff=2.00 cfs 0.096 of Subcatchment69C: Subcat 69C Runoff Area=0.817 ac 25.59% Impervious Runoff Depth>3.48" Flow Length=509' Tc=17.4 min CN=78 Runoff=3.66 cfs 0.237 of SubcatchmentSF1: Subcat SH Runoff Area=6.439 ac 6.17% Impervious Runoff Depth>3.18" Flow Length=761' Tc=23.2 min CN=75 Runoff=22.60 cfs 1.704 of SubcatchmentSF2: Subcat SF2 Runoff Area=2.408 ac 10.02% Impervious Runoff Depth>3.27" Flow Length=570' Tc=22.7 min CN=76 Runoff=8.81 cfs 0.657 of Pond 10P: pipe Peak Elev=743.58' Inflow=2.89 cfs 0.149 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0400'/' Outflow=2.89 cfs 0.149 of Pond 19P: pipe Peak Elev=686.96' Inflow=3.69 cfs 0.188 of 12.0" Round Culvert n=0.013 L=155.0' S=0.0194'/' Outflow=3.69 cfs 0.188 of Pond 29P: pipe Peak Elev=743.52' Inflow=6.54 cfs 0.252 of 12.0" Round Culvert n=0.013 L=90.0' S=0.0444'/' Outflow=6.54 cfs 0.252 of Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 3 Pond 30P: pipe Peak Elev=743.21' Inflow=20.18 cfs 0.767 of 15.0" Round Culvert n=0.013 L=220.0' S=0.0050'/' Outflow=20.18 cfs 0.767 of Pond 201 P: Forebay Peak Elev=425.51' Storage=0.252 of Inflow=87.64 cfs 5.519 of Outflow=79.15 cfs 5.412 of Pond B1.0: Existing Bioretention Peak Elev=743.57' Storage=0.084 of Inflow=5.51 cfs 0.276 of Outflow=6.54 cfs 0.252 of Pond B2.0: Existing Bioretention Peak Elev=686.98' Storage=0.081 of Inflow=11.79 cfs 0.595 of Primary=18.32 cfs 0.515 of Secondary=6.61 cfs 0.049 of Outflow=18.32 cfs 0.565 of Pond B3.0: Bioretention Peak Elev=715.53' Storage=0.021 of Inflow=1.38 cfs 0.064 of Outflow=2.21 cfs 0.055 of Pond CB13: CB13 to Expanded Wet Pond Peak Elev=462.14' Inflow=73.68 cfs 4.823 of 24.0" Round Culvert n=0.013 L=234.0' S=0.0336'/' Outflow=73.68 cfs 4.823 of Pond CB5: CB5 to ExCB11 Peak Elev=721.59' Inflow=18.58 cfs 0.967 of 18.0" Round Culvert n=0.013 L=372.0' S=0.0118'/' Outflow= 18.58 cfs 0.967 of Pond CB7: CB7 to YD2 Peak Elev=723.46' Inflow=4.26 cfs 0.238 of 12.0" Round Culvert n=0.013 L=114.0' S=0.0053'/' Outflow=4.26 cfs 0.238 of Pond CBEX2: CBEX2 to CB5 Peak Elev=722.26' Inflow=6.81 cfs 0.356 of 12.0" Round Culvert n=0.013 L=154.0' S=0.0056'/' Outflow=6.81 cfs 0.356 of Pond ExCB1 1: ExCB11 to ExCB14 Peak Elev=715.45' Inflow=46.28 cfs 2.233 of 15.0" Round Culvert n=0.013 L=280.0' S=0.0179'/' Outflow=46.28 cfs 2.233 of Pond ExCB1 4: ExCB14 to CB13 Peak Elev=637.87' Inflow=53.84 cfs 2.634 of 15.0" Round Culvert n=0.013 L=218.0' S=0.0399'/' Outflow=53.84 cfs 2.634 of Pond ExCB1A: ExCB1Ato ExCB2A Peak Elev=457.39' Inflow=1.87 cfs 0.089 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0145'/' Outflow=1.87 cfs 0.089 of Pond ExCB1 B: ExCB1 B to ExCB2B Peak Elev=500.93' Inflow=11.64 cfs 0.866 of 12.0" Round Culvert n=0.013 L=130.0' S=0.0568'/' Outflow= 11.64 cfs 0.866 of Pond ExCB2A: ExCB2A to ExCB3A Peak Elev=457.25' Inflow=4.10 cfs 0.208 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0124'/' Outflow=4.10 cfs 0.208 of Pond ExCB2B: ExCB2B to CB13 Peak Elev=481.91' Inflow=15.06 cfs 1.103 of 15.0" Round Culvert n=0.013 L=392.0' S=0.0466'/' Outflow= 15.06 cfs 1.103 of Pond ExCB3A: ExCB3A to ExCB6A Peak Elev=455.79' Inflow=12.70 cfs 0.637 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0926'/' Outflow= 12.70 cfs 0.637 of Pond ExCB4A: ExCB4A to ExCB3A Peak Elev=456.86' Inflow=5.40 cfs 0.265 of 12.0" Round Culvert n=0.013 L=73.0' S=0.0267'/' Outflow=5.40 cfs 0.265 of Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 4 Pond ExCB5A: ExCB5A to ExCB4A Peak Elev=456.88' Inflow=1.09 cfs 0.057 of 12.0" Round Culvert n=0.013 L=133.0' S=0.0259'/' Outflow=1.09 cfs 0.057 of Pond ExCB6A: ExCB6A to Expanded Wet Pond Peak Elev=445.13' Inflow=13.97 cfs 0.696 of 12.0" Round Culvert n=0.013 L=80.0' S=0.0270'/' Outflow=13.97 cfs 0.696 of Pond SMP1: Wet Pond Peak Elev=425.51' Storage=1.678 of Inflow=87.42 cfs 6.224 of Primary=2.82 cfs 1.992 of Secondary=73.62 cfs 3.621 of Outflow=76.44 cfs 5.613 of Pond YD2: YD2 to YD6 Peak Elev=723.24' Inflow=5.77 cfs 0.308 of 12.0" Round Culvert n=0.013 L=176.0' S=0.0176'/' Outflow=5.77 cfs 0.308 of Pond YD6: YD6 to CB5 Peak Elev=722.42' Inflow=6.61 cfs 0.346 of 12.0" Round Culvert n=0.013 L=40.0' S=0.0403'/' Outflow=6.61 cfs 0.346 of Link AP -1: AP -1 Inflow=94.93 cfs 7.316 of Primary=94.93 cfs 7.316 of Total Runoff Area = 25.050 ac Runoff Volume = 8.098 of Average Runoff Depth = 3.88" 64.24% Pervious = 16.091 ac 35.76% Impervious = 8.958 ac Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment 1.1: Subcat 1.1 Runoff = 1.87 cfs @ 11.98 hrs, Volume= 0.089 af, Depth> 3.89" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.180 74 >75% Grass cover, Good, HSG C 0.095 98 Paved parking, HSG C 0.275 82 Weighted Average 0.180 65.58% Pervious Area 0.095 34.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 67 0.0400 0.19 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 1.2 123 0.0590 1.70 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 7.2 190 Total Summary for Subcatchment 1.2: Subcat 1.2 Runoff = 2.29 cfs @ 11.96 hrs, Volume= 0.119 af, Depth> 5.30" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.028 74 >75% Grass cover, Good, HSG C 0.241 98 Paved parking, HSG C 0.268 96 Weighted Average 0.028 10.34% Pervious Area 0.241 89.66% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 1.3: Subcat 1.3 Runoff = 3.21 cfs @ 11.96 hrs, Volume= 0.164 af, Depth> 5.12" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 6 Area (ac) CN DescriDtion 0.057 74 >75% Grass cover, Good, HSG C 0.327 98 Paved parking, HSG C 0.384 94 Weighted Average 0.057 14.74% Pervious Area 0.327 85.26% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 1.4: Subcat 1.4 Runoff = 4.31 cfs @ 11.96 hrs, Volume= 0.209 af, Depth> 4.52" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.240 74 >75% Grass cover, Good, HSG C 0.315 98 Paved parking, HSG C 0.554 88 Weighted Average 0.240 43.23% Pervious Area 0.315 56.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 1.5: Subcat 1.5 Runoff = 1.09 cfs @ 11.96 hrs, Volume= 0.057 af, Depth> 5.30" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.009 74 >75% Grass cover, Good, HSG C 0.120 98 Paved parking, HSG C 0.128 96 Weighted Average 0.009 6.68% Pervious Area 0.120 93.32% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment 1.6: Subcat 1.6 Runoff = 1.27 cfs @ 11.97 hrs, Volume= 0.059 af, Depth> 3.89" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.121 74 >75% Grass cover, Good, HSG C 0.060 98 Paved parking, HSG C 0.182 82 Weighted Average 0.121 66.74% Pervious Area 0.060 33.26% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2: Subcat 2 Runoff = 2.02 cfs @ 11.96 hrs, Volume= 0.100 af, Depth> 4.83" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.070 74 >75% Grass cover, Good, HSG C 0.179 98 Paved parking, HSG C 0.249 91 Weighted Average 0.070 28.05% Pervious Area 0.179 71.95% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.1: Subcat 2.1 Runoff = 3.33 cfs @ 11.96 hrs, Volume= 0.161 af, Depth> 4.52" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.185 74 >75% Grass cover, Good, HSG C 0.243 98 Paved parking, HSG C 0.428 88 Weighted Average 0.185 43.21 % Pervious Area 0.243 56.79% Impervious Area Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 8 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.10: Subcat 2.10 Runoff = 6.23 cfs @ 11.96 hrs, Volume= 0.329 af, Depth> 5.45" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.001 74 >75% Grass cover, Good, HSG C 0.723 98 Paved parking, HSG C 0.725 98 Weighted Average 0.001 0.20% Pervious Area 0.723 99.80% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.11: Subcat 2.11 Runoff = 0.58 cfs @ 11.97 hrs, Volume= 0.027 af, Depth> 3.69" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.064 74 >75% Grass cover, Good, HSG C 0.022 98 Paved parking, HSG C 0.087 80 Weighted Average 0.064 74.01 % Pervious Area 0.022 25.99% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.19: Subcat 2.19 Runoff = 11.64 cfs @ 12.15 hrs, Volume= 0.866 af, Depth> 3.57" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 9 Area (ac) CN DescriDtion 0.596 74 >75% Grass cover, Good, HSG C 0.862 98 Paved parking, HSG C 1.454 70 Woods, Good, HSG C 2.912 79 Weighted Average 2.051 0.09 70.41 % Pervious Area 0.862 29.59% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 18.1 100 0.0400 0.09 Sheet Flow, 1.316 56.58% Impervious Area Woods: Light underbrush n= 0.400 P2= 2.60" 4.1 249 0.0400 1.00 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.1 20 0.0300 3.52 Shallow Concentrated Flow, Paved Kv= 20.3 fps 22.4 369 Total Summary for Subcatchment 2.2: Subcat 2.2 Runoff = 7.59 cfs @ 11.96 hrs, Volume= 0.401 af, Depth> 5.45" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.006 74 >75% Grass cover, Good, HSG C 0.877 98 Paved parking, HSG C 0.882 98 Weighted Average 0.006 0.63% Pervious Area 0.877 99.37% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.4a: Subcat 2.4a Runoff = 11.99 cfs @ 12.11 hrs, Volume= 0.853 af, Depth> 4.40" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.685 74 >75% Grass cover, Good, HSG C 1.316 98 Paved parking, HSG C 0.325 70 Woods, Good, HSG C 2.326 87 Weighted Average 1.010 43.42% Pervious Area 1.316 56.58% Impervious Area Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 10 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.9 100 0.0550 0.10 Sheet Flow, 0.144 28.52% Impervious Area Woods: Light underbrush n= 0.400 P2= 2.60" 2.0 121 0.0400 1.00 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.8 93 0.0750 1.92 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 0.7 143 0.0270 3.34 Shallow Concentrated Flow, Paved Kv= 20.3 fps 19.4 457 Total Summary for Subcatchment 2.4b: Subcat 2.4b Runoff = 1.52 cfs @ 11.96 hrs, Volume= 0.073 af, Depth> 4.41" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.090 74 >75% Grass cover, Good, HSG C 0.109 98 Paved parking, HSG C 0.199 87 Weighted Average 0.090 45.08% Pervious Area 0.109 54.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.4c: Subcat 2.4c Runoff = 3.34 cfs @ 11.97 hrs, Volume= 0.155 af, Depth> 3.69" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.251 74 >75% Grass cover, Good, HSG C 0.144 98 Paved parking, HSG C 0.109 70 Woods, Good, HSG C 0.505 80 Weighted Average 0.361 71.48% Pervious Area 0.144 28.52% Impervious Area Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 11 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 76 0.0789 0.25 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 1.2 244 0.0492 3.33 Shallow Concentrated Flow, Grassed Waterwav Kv= 15.0 fps 6.2 320 Total Summary for Subcatchment 2.5: Subcat 2.5 Runoff = 1.36 cfs @ 11.97 hrs, Volume= 0.064 af, Depth> 4.10" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.110 74 >75% Grass cover, Good, HSG C 0.078 98 Paved parking, HSG C 0.188 84 Weighted Average 0.110 58.34% Pervious Area 0.078 41.66% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.6a: Subcat 2.6a Runoff = 1.38 cfs @ 11.97 hrs, Volume= 0.064 af, Depth> 4.00" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.119 74 >75% Grass cover, Good, HSG C 0.074 98 Paved parking, HSG C 0.193 83 Weighted Average 0.119 61.65% Pervious Area 0.074 38.35% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.7: Subcat 2.7 Runoff = 2.36 cfs @ 11.96 hrs, Volume= 0.125 af, Depth> 5.45" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 12 Area (ac) CN Description 0.000 74 >75% Grass cover, Good, HSG C 0.274 98 Paved parking, HSG C 0.274 98 Weighted Average 0.000 0.07% Pervious Area 0.274 99.93% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 3: Subcat 3 Runoff = 2.89 cfs @ 11.96 hrs, Volume= 0.149 af, Depth> 5.22" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.048 74 >75% Grass cover, Good, HSG C 0.295 98 Paved parking, HSG C 0.343 95 Weighted Average 0.048 14.01 % Pervious Area 0.295 85.99% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 4: Subcat 4 Runoff = 8.25 cfs @ 12.00 hrs, Volume= 0.407 af, Depth> 3.79" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.345 74 >75% Grass cover, Good, HSG C 0.440 98 Paved parking, HSG C 0.506 70 Woods, Good, HSG C 1.290 81 Weighted Average 0.851 65.92% Pervious Area 0.440 34.08% Impervious Area Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 13 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.0 100 0.0600 0.24 Sheet Flow, 0.124 2.3 149 27.63% Impervious Area 1.06 Grass: Short n= 0.150 P2= 2.60" 0.2 66 0.0610 5.01 Shallow Concentrated Flow, Paved Kv= 20.3 fps 1.3 147 0.0750 1.92 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 8.5 313 Tota Summary for Subcatchment 5: Subcat 5 Runoff = 2.50 cfs @ 12.03 hrs, Volume= 0.137 af, Depth> 3.68" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.283 74 >75% Grass cover, Good, HSG C 0.124 98 Paved parking, HSG C 0.041 70 Woods, Good, HSG C 0.448 80 Weighted Average 0.324 72.37% Pervious Area 0.124 2.3 149 27.63% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.5 100 0.0280 0.18 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 2.3 149 0.0230 1.06 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 11.8 249 Total Summary for Subcatchment 6: Subcat 6 Runoff = 1.53 cfs @ 11.97 hrs, Volume= 0.070 af, Depth> 3.49" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.199 74 >75% Grass cover, Good, HSG C 0.042 98 Paved parking, HSG C 0.241 78 Weighted Average 0.199 82.56% Pervious Area 0.042 17.44% Impervious Area Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 14 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 7: Subcat 7 Runoff = 0.85 cfs @ 11.97 hrs, Volume= 0.038 af, Depth> 3.19" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.137 74 >75% Grass cover, Good, HSG C 0.007 98 Paved parking, HSG C 0.144 75 Weighted Average 0.137 95.17% Pervious Area 0.007 4.83% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 8: Subcat 8 Runoff = 0.98 cfs @ 11.98 hrs, Volume= 0.045 af, Depth> 3.59" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.118 74 >75% Grass cover, Good, HSG C 0.033 98 Paved parking, HSG C 0.151 79 Weighted Average 0.118 78.37% Pervious Area 0.033 21.63% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.2 100 0.0800 0.27 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 0.3 33 0.0910 2.11 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 6.5 133 Total Summary for Subcatchment 9: Subcat 9 Runoff = 6.85 cfs @ 11.96 hrs, Volume= 0.329 af, Depth> 4.41" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 15 Area (ac) CN Description 0.383 74 >75% Grass cover, Good, HSG C 0.479 98 Paved parking, HSG C 0.032 70 Woods, Good, HSG C 0.895 87 Weighted Average 0.416 46.43% Pervious Area 0.479 53.57% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 10: Subcat 10 Runoff = 3.69 cfs @ 11.96 hrs, Volume= 0.188 af, Depth> 5.12" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.074 74 >75% Grass cover, Good, HSG C 0.367 98 Paved parking, HSG C 0.441 94 Weighted Average 0.074 16.72% Pervious Area 0.367 83.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 11: Subcat 11 Runoff = 2.69 cfs @ 11.98 hrs, Volume= 0.127 af, Depth> 3.69" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.149 74 >75% Grass cover, Good, HSG C 0.123 98 Paved parking, HSG C 0.141 70 Woods, Good, HSG C 0.412 80 Weighted Average 0.289 70.18% Pervious Area 0.123 29.82% Impervious Area Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 16 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 100 0.0900 0.28 Sheet Flow, 0.608 74.41 % Pervious Area Grass: Short n= 0.150 P2= 2.60" 1.1 87 0.0340 1.29 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 7.1 187 Total Summary for Subcatchment 12: Subcat 12 Runoff = 2.00 cfs @ 11.96 hrs, Volume= 0.096 af, Depth> 4.41" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.120 74 >75% Grass cover, Good, HSG C 0.142 98 Paved parking, HSG C 0.262 87 Weighted Average 0.120 45.76% Pervious Area 0.142 54.24% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 69C: Subcat 69C Runoff = 3.66 cfs @ 12.10 hrs, Volume= 0.237 af, Depth> 3.48" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.071 74 >75% Grass cover, Good, HSG C 0.209 98 Paved parking, HSG C 0.537 70 Woods, Good, HSG C 0.817 78 Weighted Average 0.608 74.41 % Pervious Area 0.209 25.59% Impervious Area Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 18 Area (ac) CN DescriDtion 0.462 74 >75% Grass cover, Good, HSG C 0.442 80 >75% Grass cover, Good, HSG D 0.241 98 Paved parking, HSG C 1.122 70 Woods, Good, HSG C 0.141 77 Woods, Good, HSG D 2.408 76 Weighted Average 2.167 Shallow Concentrated Flow, 89.98% Pervious Area 0.241 10.02% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 16.5 100 0.0500 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.60" 6.2 470 0.0638 1.26 Shallow Concentrated Flow, Woodland Kv= 5.0 fDs 22.7 570 Total Summary for Pond 10P: pipe Inflow Area = 0.343 ac, 85.99% Impervious, Inflow = 2.89 cfs @ 11.96 hrs, Volume Outflow = 2.89 cfs @ 11.96 hrs, Volume Primary = 2.89 cfs @ 11.96 hrs, Volume Inflow Depth > 5.22" = 0.149 of = 0.149 af, = 0.149 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 743.58' @ 12.20 hrs Device Routing Invert Outlet Devices #1 Primary 470.00' 12.0" Round Culvert L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 470.00'/ 468.00' S= 0.0400 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=2.83 cfs @ 11.96 hrs HW=471.06' TW=466.53' (Dynamic Tailwater) Ll =Culvert (Inlet Controls 2.83 cfs @ 3.60 fps) Summary for Pond 19P: pipe Inflow Area = 0.441 ac, 83.28% Impervious, Inflow = 3.69 cfs @ 11.96 hrs, Volume Outflow = 3.69 cfs @ 11.96 hrs, Volume Primary = 3.69 cfs @ 11.96 hrs, Volume Inflow Depth > 5.12" = 0.188 of = 0.188 af, = 0.188 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 686.96' @ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 465.00' 12.0" Round Culvert L= 155.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 465.00'/462.00' S=0.0194'/' Cc= 0.900 Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 19 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.96 hrs HW=477.02' TW=518.46' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond 29P: pipe Inflow Area = 0.755 ac, 55.31 % Impervious, Inflow = 6.54 cfs @ 12.37 hrs, Volume Outflow = 6.54 cfs @ 12.37 hrs, Volume Primary = 6.54 cfs @ 12.37 hrs, Volume Inflow Depth > 4.01" = 0.252 of = 0.252 af, = 0.252 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 743.52' @ 12.10 hrs Device Routing Invert Outlet Devices #1 Primary 461.00' 12.0" Round Culvert L= 90.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 461.00'/ 457.00' S= 0.0444 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=5.45 cfs @ 12.37 hrs HW=464.59' TW=461.35' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 5.45 cfs @ 6.94 fps) Summary for Pond 30P: pipe Inflow Area = 2.486 ac, 49.25% Impervious, Inflow = 20.18 cfs @ 12.05 hrs, Volume Outflow = 20.18 cfs @ 12.05 hrs, Volume Primary = 20.18 cfs @ 12.05 hrs, Volume Inflow Depth > 3.70" = 0.767 of = 0.767 af, = 0.767 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 743.21' @ 12.05 hrs Device Routing Invert Outlet Devices #1 Primary 456.50' 15.0" Round Culvert L= 220.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 456.50'/455.40' S=0.0050'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Primary OutFlow Max=29.59 cfs @ 12.05 hrs HW=740.70' TW=680.82' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 29.59 cfs @ 24.12 fps) Summary for Pond 201 P: Forebay Inflow Area = 15.697 ac, 52.08% Impervious, Inflow = 87.64 cfs @ 11.96 hrs, Volume Outflow = 79.15 cfs @ 11.95 hrs, Volume Primary = 79.15 cfs @ 11.95 hrs, Volume Inflow Depth > 4.22" = 5.519 of = 5.412 af, = 5.412 of for 100 -year event Atten= 10%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADOO 10.00-21 s/n 004390 2018 HydroCAD Software Solutions LLC Page 20 Starting Elev= 422.00' Surf.Area= 0.043 ac Storage= 0.049 of Peak Elev= 425.51' @ 12.11 hrs Surf.Area= 0.096 ac Storage= 0.252 of (0.203 of above start) Plug -Flow detention time= 19.4 min calculated for 5.363 of (97% of inflow) Center -of -Mass det. time= 4.0 min (767.1 - 763.1 ) Volume Invert Avail.Storage Storage Description #1 419.00' 0.252 of Custom Stage Data (Irregular)Listed below (Recalc) Elevation (feet) Surf.Area (acres) Perim. (feet) Inc.Store (acre-feet) Cum.Store (acre-feet) Wet.Area (acres) 419.00 0.002 35.0 0.000 0.000 0.002 420.00 0.009 77.0 0.005 0.005 0.011 421.00 0.019 107.0 0.014 0.019 0.021 422.00 0.043 158.0 0.030 0.049 0.046 423.00 0.058 182.0 0.050 0.099 0.061 424.00 0.076 207.0 0.067 0.166 0.080 425.00 0.096 232.0 0.086 0.252 0.100 Device Routing Invert Outlet Devices #1 Primary 422.00' 25.0' long x 8.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64 2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74 Primary OutFlow Max=0.00 cfs @ 11.95 hrs HW=424.82' TW=425.09' (Dynamic Tailwater) Ll =Broad -Crested Rectangular Weir(Controls 0.00 cfs) Summary for Pond B1.0: Existing Bioretention Inflow Area = 0.755 ac, 55.31 % Impervious, Inflow = 5.51 cfs @ 11.97 hrs, Volume Outflow = 6.54 cfs @ 12.37 hrs, Volume Primary = 6.54 cfs @ 12.37 hrs, Volume Inflow Depth > 4.38" for 100 -year event = 0.276 of = 0.252 af, Atten= 0%, Lag= 23.6 min = 0.252 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 743.57' @ 12.15 hrs Surf.Area= 0.064 ac Storage= 0.084 of Plug -Flow detention time= 54.0 min calculated for 0.252 of (91 % of inflow) Center -of -Mass det. time= 23.0 min (776.0 - 753.0 ) Volume Invert Avail.Storage Storage Description #1 465.00' 0.084 of Custom Stage Data (Prismatic)Listed below (Recalc) Elevation SurF.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) 465.00 0.026 0.000 0.000 466.00 0.039 0.032 0.032 467.00 0.064 0.051 0.084 Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 21 Device Routing Invert Outlet Devices #1 Primary 465.00' 1.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 465.75' 15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=5.81 cfs @ 12.37 hrs HW=466.70' TW=464.59' (Dynamic Tailwater) � 1=Exfiltration (Exfiltration Controls 0.06 cfs) 2=Orifice/Grate (Orifice Controls 5.75 cfs @ 4.69 fps) Summary for Pond B2.0: Existing Bioretention Inflow Area = 1.731 ac, 46.61 % Impervious, Inflow Depth > 4.13" for 100 -year event Inflow = 11.79 cfs @ 11.99 hrs, Volume= 0.595 of Outflow = 18.32 cfs @ 11.95 hrs, Volume= 0.565 af, Atten= 0%, Lag= 0.0 min Primary = 18.32 cfs @ 11.95 hrs, Volume= 0.515 of Secondary = 6.61 cfs @ 12.15 hrs, Volume= 0.049 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 686.98' @ 12.04 hrs Surf.Area= 0.087 ac Storage= 0.081 of Plug -Flow detention time= 35.9 min calculated for 0.565 of (95% of inflow) Center -of -Mass det. time= 16.0 min ( 777.3 - 761.3 ) Volume Invert Avail.Storage Storage Description #1 459.50' 0.081 of Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) 459.50 0.029 0.000 0.000 460.00 0.040 0.017 0.017 461.00 0.087 0.063 0.081 Device Routing Invert Outlet Devices #1 Primary 459.50' 1.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 460.25' 15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Secondary 460.75' 20.0' long x 1.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 Primary OutFlow Max=0.09 cfs @ 11.95 hrs HW=510.34' TW=559.81' (Dynamic Tailwater) � 1=Exfiltration (Exfiltration Controls 0.09 cfs) 2=Orifice/Grate (Controls 0.00 cfs) Secondary OutFlow Max=85,361.71 cfs @ 12.15 hrs HW=582.41' TW=487.92' (Dynamic Tailwater) L3=B road -Crested Rectangular Weir (Weir Controls 85,361.71 cfs @ 35.08 fps) Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 22 Summary for Pond B3.0: Bioretention Inflow Area = 0.193 ac, 38.35% Impervious, Inflow = 1.38 cfs @ 11.97 hrs, Volume Outflow = 2.21 cfs @ 12.55 hrs, Volume Primary = 2.21 cfs @ 12.55 hrs, Volume Inflow Depth > 4.00" = 0.064 of = 0.055 af, = 0.055 of for 100 -year event Atten= 0%, Lag= 35.2 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 715.53' @ 12.05 hrs Surf.Area= 0.030 ac Storage= 0.021 of Plug -Flow detention time= 78.1 min calculated for 0.055 of (86% of inflow) Center -of -Mass det. time= 35.6 min (801.0 - 765.4 ) Volume Invert Avail.Storage Storage Description #1 447.20' 0.021 of Custom Stage Data (Irregular)Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (acres) (feet) (acre-feet) (acre-feet) (acres) 447.20 0.014 102.0 0.000 0.000 0.014 448.20 0.030 152.0 0.021 0.021 0.037 Device Routing Invert Outlet Devices #1 Primary 445.45' 12.0" Round Culvert L= 75.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 445.45'/444.95' S=0.0067'/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2 Device 1 447.45' 1.000 in/hr Exfiltration over Surface area above 447.45' Excluded Surface area = 0.017 ac #3 Device 1 447.70' 12.0" Horiz. Yard Drain C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=2.05 cfs @ 12.55 hrs HW=448.04' TW=446.73' (Dynamic Tailwater) Ll =Culvert (Passes 2.05 cfs of 3.68 cfs potential flow) � 2=Exfiltration (Exfiltration Controls 0.01 cfs) 3=Yard Drain (Weir Controls 2.04 cfs @ 1.91 fps) Summary for Pond CB13: CB13 to Expanded Wet Pond Inflow Area = 13.906 ac, 50.47% Impervious, Inflow = 73.68 cfs @ 11.96 hrs, Volume Outflow = 73.68 cfs @ 11.96 hrs, Volume Primary = 73.68 cfs @ 11.96 hrs, Volume Inflow Depth > 4.16" = 4.823 of = 4.823 af, = 4.823 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 462.14' @ 11.96 hrs Device Routing Invert Outlet Devices #1 Primary 430.76' 24.0" Round Culvert L= 234.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 430.76'/422.90' S=0.0336'/' Cc= 0.900 n= 0.013, Flow Area= 3.14 sf Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 23 Primary OutFlow Max=70.46 cfs @ 11.96 hrs HW=459.40' TW=424.88' (Dynamic Tailwater) Ll =Culvert (Barrel Controls 70.46 cfs @ 22.43 fps) Summary for Pond CB5: CB5 to ExCB11 Inflow Area = 2.580 ac, 59.95% Impervious, Inflow = 18.58 cfs @ 11.97 hrs, Volume Outflow = 18.58 cfs @ 11.97 hrs, Volume Primary = 18.58 cfs @ 11.97 hrs, Volume Inflow Depth > 4.50" = 0.967 of = 0.967 af, = 0.967 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 721.59' @ 12.05 hrs Device Routing Invert Outlet Devices #1 Primary 449.34' 18.0" Round Culvert L= 372.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 449.34'/444.95' S=0.0118'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf Primary OutFlow Max=0.00 cfs @ 11.97 hrs HW=600.98' TW=691.32' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond CB7: CB7 to YD2 Inflow Area = 0.697 ac, 43.48% Impervious, Inflow = 4.26 cfs @ 11.99 hrs, Volume Outflow = 4.26 cfs @ 11.99 hrs, Volume Primary = 4.26 cfs @ 11.99 hrs, Volume Inflow Depth > 4.09" = 0.238 of = 0.238 af, = 0.238 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 723.46' @ 12.20 hrs Device Routing Invert Outlet Devices #1 Primary 456.00' 12.0" Round Culvert L= 114.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 456.00'/455.40' S=0.0053'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.99 hrs HW=479.78' TW=509.92' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond CBEX2: CBEX2 to CB5 Inflow Area = 0.811 ac, 91.92% Impervious, Inflow Depth > 5.26" for 100 -year event Inflow = 6.81 cfs @ 11.96 hrs, Volume= 0.356 of Outflow = 6.81 cfs @ 11.96 hrs, Volume= 0.356 af, Atten= 0%, Lag= 0.0 min Primary = 6.81 cfs @ 11.96 hrs, Volume= 0.356 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 24 Peak Elev= 722.26' @ 12.10 hrs Device Routing Invert Outlet Devices #1 Primary 450.30' 12.0" Round Culvert L= 154.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 450.30'/449.44' S=0.0056'/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.96 hrs HW=521.58' TW=577.69' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB11: ExCB11 to ExCB14 Inflow Area = 6.342 ac, 53.65% Impervious, Inflow = 46.28 cfs @ 11.95 hrs, Volume Outflow = 46.28 cfs @ 11.95 hrs, Volume Primary = 46.28 cfs @ 11.95 hrs, Volume Inflow Depth > 4.23" = 2.233 of = 2.233 af, = 2.233 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 715.45' @ 12.00 hrs Device Routing Invert Outlet Devices #1 Primary 444.90' 15.0" Round Culvert L= 280.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 444.90'/439.90' S=0.0179'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Primary OutFlow Max=24.67 cfs @ 11.95 hrs HW=678.93' TW=628.56' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 24.67 cfs @ 20.10 fps) Summary for Pond ExCB14: ExCB14 to CB13 Inflow Area = 7.224 ac, 59.24% Impervious, Inflow = 53.84 cfs @ 11.96 hrs, Volume Outflow = 53.84 cfs @ 11.96 hrs, Volume Primary = 53.84 cfs @ 11.96 hrs, Volume Inflow Depth > 4.37" = 2.634 of = 2.634 af, = 2.634 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 637.87' @ 11.96 hrs Device Routing Invert Outlet Devices #1 Primary 439.60' 15.0" Round Culvert L= 218.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 439.60'/ 430.90' S= 0.0399 T Cc= 0.900 n= 0.013, Flow Area= 1.23 sf Primary OutFlow Max=49.66 cfs @ 11.96 hrs HW=628.03' TW=460.62' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 49.66 cfs @ 40.47 fps) Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 25 Summary for Pond ExCB1A: ExCB1A to ExCB2A Inflow Area = 0.275 ac, 34.42% Impervious, Inflow = 1.87 cfs @ 11.98 hrs, Volume Outflow = 1.87 cfs @ 11.98 hrs, Volume Primary = 1.87 cfs @ 11.98 hrs, Volume Inflow Depth > 3.89" = 0.089 of = 0.089 af, = 0.089 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 457.39' @ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 436.50' 12.0" Round Culvert L= 186.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.50'/433.80' S=0.0145'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.98 hrs HW=441.29' TW=449.12' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB1B: ExCB1B to ExCB2B Inflow Area = 2.912 ac, 29.59% Impervious, Inflow = 11.64 cfs @ 12.15 hrs, Volume Outflow = 11.64 cfs @ 12.15 hrs, Volume Primary = 11.64 cfs @ 12.15 hrs, Volume Inflow Depth > 3.57" = 0.866 of = 0.866 af, = 0.866 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 500.93' @ 12.15 hrs Device Routing Invert Outlet Devices #1 Primary 457.15' 12.0" Round Culvert L= 130.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 457.15'/449.76' S=0.0568'/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=15.99 cfs @ 12.15 hrs HW=499.86' TW=463.94' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 15.99 cfs @ 20.36 fps) Summary for Pond ExCB2A: ExCB2A to ExCB3A Inflow Area = 0.543 ac, 61.71 % Impervious, Inflow = 4.10 cfs @ 11.97 hrs, Volume Outflow = 4.10 cfs @ 11.97 hrs, Volume Primary = 4.10 cfs @ 11.97 hrs, Volume Inflow Depth > 4.59" = 0.208 of = 0.208 af, = 0.208 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 457.25' @ 12.04 hrs Device Routing Invert Outlet Devices #1 Primary 433.70' 12.0" Round Culvert L= 186.0' CPP, square edge headwall, Ke= 0.500 Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 26 Inlet/ Outlet Invert= 433.70'/431.40' S=0.0124'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.97 hrs HW=446.81' TW=452.29' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB2B: ExCB2B to CB13 Inflow Area = 3.729 ac, 28.71 % Impervious, Inflow = 15.06 cfs @ 12.14 hrs, Volume Outflow = 15.06 cfs @ 12.14 hrs, Volume Primary = 15.06 cfs @ 12.14 hrs, Volume Inflow Depth > 3.55" = 1.103 of = 1.103 af, = 1.103 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 481.91' @ 12.10 hrs Device Routing Invert Outlet Devices #1 Primary 449.50' 15.0" Round Culvert L= 392.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 449.50'/431.24' S=0.0466'/' Cc= 0.900 n= 0.013, Flow Area= 1.23 sf Primary OutFlow Max=16.28 cfs @ 12.14 hrs HW=468.85' TW=439.78' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 16.28 cfs @ 13.26 fps) Summary for Pond ExCB3A: ExCB3A to ExCB6A Inflow Area = 1.610 ac, 68.15% Impervious, Inflow = 12.70 cfs @ 11.97 hrs, Volume Outflow = 12.70 cfs @ 11.97 hrs, Volume Primary = 12.70 cfs @ 11.97 hrs, Volume Inflow Depth > 4.75" = 0.637 of = 0.637 af, = 0.637 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 455.79' @ 12.00 hrs Device Routing Invert Outlet Devices #1 Primary 431.30' 12.0" Round Culvert L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 431.30'/ 426.67' S= 0.0926 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=9.79 cfs @ 11.97 hrs HW=451.57' TW=444.16' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 9.79 cfs @ 12.46 fps) Summary for Pond ExCB4A: ExCB4A to ExCB3A Inflow Area = 0.683 ac, 63.65% Impervious, Inflow Depth > 4.67" Inflow = 5.40 cfs @ 11.96 hrs, Volume= 0.265 of Outflow = 5.40 cfs @ 11.96 hrs, Volume= 0.265 af, Primary = 5.40 cfs @ 11.96 hrs, Volume= 0.265 of for 100 -year event Atten= 0%, Lag= 0.0 min Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 27 Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 456.86' @ 12.04 hrs Device Routing Invert Outlet Devices #1 Primary 433.35' 12.0" Round Culvert L= 73.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 433.35'/431.40' S=0.0267'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.96 hrs HW=444.94' TW=451.34' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB5A: ExCB5A to ExCB4A Inflow Area = 0.128 ac, 93.32% Impervious, Inflow = 1.09 cfs @ 11.96 hrs, Volume Outflow = 1.09 cfs @ 11.96 hrs, Volume Primary = 1.09 cfs @ 11.96 hrs, Volume Inflow Depth > 5.30" = 0.057 of = 0.057 af, = 0.057 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 456.88' @ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 436.80' 12.0" Round Culvert L= 133.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.80'/433.35' S=0.0259'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.96 hrs HW=438.72' TW=444.55' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB6A: ExCB6A to Expanded Wet Pond Inflow Area = 1.791 ac, 64.61% Impervious, Inflow = 13.97 cfs @ 11.97 hrs, Volume Outflow = 13.97 cfs @ 11.97 hrs, Volume Primary = 13.97 cfs @ 11.97 hrs, Volume Inflow Depth > 4.66" = 0.696 of = 0.696 af, = 0.696 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 445.13' @ 11.97 hrs Device Routing Invert Outlet Devices #1 Primary 426.67' 12.0" Round Culvert L= 80.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 426.67'/424.51' S=0.0270'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=13.59 cfs @ 11.97 hrs HW=444.16' TW=424.91' (Dynamic Tailwater) L1=Culvert (Barrel Controls 13.59 cfs @ 17.30 fps) Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 28 Summary for Pond SMP1: Wet Pond Inflow Area = 18.611 ac, 46.00% Impervious, Inflow Depth > 4.01 " for 100 -year event Inflow = 87.42 cfs @ 12.05 hrs, Volume= 6.224 of Outflow = 76.44 cfs @ 12.06 hrs, Volume= 5.613 af, Atten= 13%, Lag= 0.8 min Primary = 2.82 cfs @ 12.06 hrs, Volume= 1.992 of Secondary = 73.62 cfs @ 12.06 hrs, Volume= 3.621 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 421.60' Surf.Area= 0.215 ac Storage= 0.451 of Peak Elev= 425.51' @ 12.06 hrs Surf.Area= 0.419 ac Storage= 1.678 of (1.227 of above start) Plug -Flow detention time= 90.3 min calculated for 5.144 of (83% of inflow) Center -of -Mass det. time= 24.6 min ( 794.5 - 769.9 ) Volume Invert Avail.Storage Storage Description #1 418.50' 2.120 of Custom Stage Data (Irregular)Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (acres) (feet) (acre-feet) (acre-feet) (acres) 418.50 0.080 439.0 0.000 0.000 0.080 419.00 0.100 452.0 0.045 0.045 0.101 420.00 0.143 477.0 0.121 0.165 0.145 421.00 0.188 502.0 0.165 0.330 0.191 422.00 0.235 527.0 0.211 0.541 0.240 423.00 0.284 552.0 0.259 0.800 0.290 424.00 0.336 577.0 0.310 1.110 0.344 425.00 0.390 603.0 0.363 1.473 0.401 426.00 0.447 628.0 0.418 1.891 0.459 426.50 0.466 631.0 0.228 2.120 0.469 Device Routing Invert Outlet Devices #1 Primary 420.67' 8.0" Round Culvert L= 110.0' CPP, end -section conforming to fill, Ke= 0.500 Inlet / Outlet Invert= 420.67'/ 417.32' S= 0.0305 T Cc= 0.900 n= 0.013, Flow Area= 0.35 sf #2 Device 1 421.50' 7.0" W x 6.0" H Vert. Orifice/Grate C= 0.600 #3 Device 1 424.00' 24.0" x 24.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Secondary 424.00' 15.0' long x 10.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=2.82 cfs @ 12.06 hrs HW=425.49' TW=0.00' (Dynamic Tailwater) Ll =Culvert (Barrel Controls 2.82 cfs @ 8.06 fps) � 2=Orifice/Grate (Passes < 2.72 cfs potential flow) 3=Orifice/Grate (Passes < 23.51 cfs potential flow) Secondary OutFlow Max=72.44 cfs @ 12.06 hrs HW=425.49' TW=0.00' (Dynamic Tailwater) =Broad -Crested Rectangular Weir (Weir Controls 72.44 cfs @ 3.24 fps) Pre-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/2/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 29 Summary for Pond YD2: YD2 to YD6 Inflow Area = 0.938 ac, 36.80% Impervious, Inflow = 5.77 cfs @ 11.99 hrs, Volume Outflow = 5.77 cfs @ 11.99 hrs, Volume Primary = 5.77 cfs @ 11.99 hrs, Volume Inflow Depth > 3.94" = 0.308 of = 0.308 af, = 0.308 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 723.24' @ 12.15 hrs Device Routing Invert Outlet Devices #1 Primary 455.30' 12.0" Round Culvert L= 176.0' Ke= 0.500 Inlet/ Outlet Invert= 455.30'/452.21' S=0.0176'/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.99 hrs HW=504.45' TW=535.02' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond YD6: YD6 to CB5 Inflow Area = 1.081 ac, 32.55% Impervious, Inflow = 6.61 cfs @ 11.98 hrs, Volume Outflow = 6.61 cfs @ 11.98 hrs, Volume Primary = 6.61 cfs @ 11.98 hrs, Volume Inflow Depth > 3.84" = 0.346 of = 0.346 af, = 0.346 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 722.42' @ 12.10 hrs Device Routing Invert Outlet Devices #1 Primary 452.11' 12.0" Round Culvert L= 40.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 452.11'/450.50' S=0.0403'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.98 hrs HW=533.30' TW=640.61' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Link AP -1: AP -1 Inflow Area = 25.050 ac, 35.76% Impervious, Inflow Depth > 3.50" for 100 -year event Inflow = 94.93 cfs @ 12.08 hrs, Volume= 7.316 of Primary = 94.93 cfs @ 12.08 hrs, Volume= 7.316 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Attachment C Proposed Conditions Watershed Map and HydroCAD Calculations c'Jia .0 11 01. 1? h 0 c) Ln 0 4- L�2 ro t — z 12 [2 V) co < 0 0 < < 0 3 5 0 0 < —vr— tl 0 — — — — — —LL cn l(ompvojy t1PON < — _ 72 w XOMPO,G_ 00, -9ts 11 '10 .400� oe, �x 11 qvvv f5— -- — — — — — — -- -21 4� ST j V 0 VX O j—, OU) Ln I ', t�—� \XE ��\�`— � 'F\ - —� /` \ � l sn \\�\/_-- - � �—asoma � �� 11 ` �E �\\ Fe` � LOI ��-Vd LIVH�V 211 �Lm I 3.005�- El s V� f/ K\ oa 19, f--7 1 �'—o_ ��� �\-i�� ~ ��—e<n� 1 �� _�\�\ \ ��\ � /��N/ I � � / £96=� \ �ISYJ `\ � \ �G�w R ` I >s --------------------VIII 40' �g Post-Dev Skidmore Swing Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 6.396 74 >75% Grass cover, Good, HSG C (1.11 1.21 1.31 1.41 1.51 1.61 21 2.1) 2.101 2.111 2.191 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.7, 31 4, 51 61 7, 81 91 10, 11, 12, 69C, SF1, SF2, SF3, SF3a, SF4, SF4a, SF5, SF6, SF7) 0.768 80 >75% Grass cover, Good, HSG D (SF1, SF2, SF7) 9.598 98 Paved parking, HSG C (1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 212.11 2.10, 2.11, 2.191 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.7, 31 41 51 61 7) 81 91 101 11, 12, 69C, SF1, SF2, SF3, SF3a, SF4a, SF5, SF6, SF7) 0.011 98 Paved parking, HSG D (SF1) 5.713 70 Woods, Good, HSG C (2.19,2.4a, 2.4c, 4, 5, 9, 11, 69C, SF1, SF2, SF3, SF4, SF4a, SF6, SF7) 2.565 77 Woods, Good, HSG D (SF1, SF2, SF4, SF7) 25.050 83 TOTAL AREA Post-Dev Skidmore Swing Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 3 Soil Listing (all nodes) Area Soil Subcatchment (acres) Group Numbers 0.000 HSG A 0.000 HSG B 21.706 HSG C 1.11 1.21 1.31 1.41 1.51 1.61 21 2.11 2.101 2.111 2.191 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.71 31 41 51 61 71 8, 91 101 111121 69C, S F 1, S F2, S F3, SF3a, S F4, S F4a, S F5, SF6, SF7 3.344 HSG D SF1, SF2, SF4, SF7 0.000 Other 25.050 TOTAL AREA Post-Dev Skidmore Swing Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 4 Ground Covers (all nodes) HSG -A HSG -B HSG -C HSG -D Other Total Ground Subcatchment (acres) (acres) (acres) (acres) (acres) (acres) Cover Numbers 0.000 0.000 6.396 0.768 0.000 7.164 >75% Grass cover, Good 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2)2.1) 2.10, 2.11, 2.19, 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.7, 3, 4, 5, 6, 7)8A 9, 10, 11, 12, 69C, SF1, S F2, SF3, SF3a, SF4, S F4a, SF5, SF6, SF7 0.000 0.000 9.598 0.011 0.000 9.609 Paved parking 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 2)2.1) 2.10, 2.11, 2.19, 2.2, 2.4a, 2.4b, 2.4c, 2.5, 2.6a, 2.7, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 69C, SF1, SF2, SF3, SF3a, S F4a, SF5, SF6, SF7 Post-Dev Skidmore Swing Prepared by The LA Group Printed 4/12/2019 HydroCADOO 10.00-21 s/n 004390 2018 HydroCAD Software Solutions LLC Page 5 Ground Covers (all nodes) (continued) HSG -A HSG -B HSG -C HSG -D Other Total Ground Subcatchment (acres) (acres) (acres) (acres) (acres) (acres) Cover Numbers 0.000 0.000 5.713 2.565 0.000 8.277 Woods, Good 2.191 2.4a, 2.4c, 4, 5191 11, 69C, SF1, SF2, SF3, SF4, SF4a, SF6, SF7 0.000 0.000 21.706 3.344 0.000 25.050 TOTAL AREA Post-Dev Skidmore Swing Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 6 Pipe Listing (all nodes) Line# Node Number In -Invert (feet) Out -Invert (feet) Length (feet) Slope (ft/ft) n Diam/Width (inches) Height (inches) Inside -Fill (inches) 1 2P 446.90 446.70 25.0 0.0080 0.013 15.0 0.0 0.0 2 5P 449.60 447.60 262.0 0.0076 0.013 12.0 0.0 0.0 3 6P 447.50 447.00 10.0 0.0500 0.013 15.0 0.0 0.0 4 7P 449.00 447.60 182.0 0.0077 0.013 12.0 0.0 0.0 5 10P 470.00 468.00 50.0 0.0400 0.013 12.0 0.0 0.0 6 19P 465.00 462.00 155.0 0.0194 0.013 12.0 0.0 0.0 7 29P 461.00 457.00 90.0 0.0444 0.013 12.0 0.0 0.0 8 30P 456.50 455.40 220.0 0.0050 0.013 15.0 0.0 0.0 9 B3.0 445.45 444.95 75.0 0.0067 0.013 12.0 0.0 0.0 10 CB13 430.76 422.90 234.0 0.0336 0.013 24.0 0.0 0.0 11 CB5 449.34 444.95 372.0 0.0118 0.013 18.0 0.0 0.0 12 CB7 456.00 455.40 114.0 0.0053 0.013 12.0 0.0 0.0 13 CBEX2 450.30 449.44 154.0 0.0056 0.013 12.0 0.0 0.0 14 ExCB11 444.90 439.90 280.0 0.0179 0.013 15.0 0.0 0.0 15 ExCB14 439.60 430.90 218.0 0.0399 0.013 15.0 0.0 0.0 16 ExCB1A 436.50 433.80 186.0 0.0145 0.013 12.0 0.0 0.0 17 ExCB1 B 457.15 449.76 130.0 0.0568 0.013 12.0 0.0 0.0 18 ExCB2A 433.70 431.40 186.0 0.0124 0.013 12.0 0.0 0.0 19 ExCB2B 449.50 431.24 392.0 0.0466 0.013 15.0 0.0 0.0 20 ExCB3A 431.30 426.67 50.0 0.0926 0.013 12.0 0.0 0.0 21 ExCB4A 433.35 431.40 73.0 0.0267 0.013 12.0 0.0 0.0 22 ExCB5A 436.80 433.35 133.0 0.0259 0.013 12.0 0.0 0.0 23 ExCB6A 426.67 424.51 80.0 0.0270 0.013 12.0 0.0 0.0 24 SMP -2 420.67 417.32 110.0 0.0305 0.013 8.0 0.0 0.0 25 YD2 455.30 452.21 176.0 0.0176 0.013 12.0 0.0 0.0 26 YD6 452.11 450.50 40.0 0.0403 0.013 12.0 0.0 0.0 Post-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 7 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS, Weighted -CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1.1: Subcat 1.1 Runoff Area=0.275 ac 34.42% Impervious Runoff Depth>0.68" Flow Length=190' Tc=7.2 min CN=82 Runoff=0.34 cfs 0.016 of Subcatchment 1.2: Subcat 1.2 Runoff Area=0.268 ac 89.66% Impervious Runoff Depth>1.61" Tc=6.0 min CN=96 Runoff=0.74 cfs 0.036 of Subcatchment 1.3: Subcat 1.3 Runoff Area=0.384 ac 85.26% Impervious Runoff Depth>1.44" Tc=6.0 min CN=94 Runoff=0.97 cfs 0.046 of Subcatchment 1.4: Subcat 1.4 Runoff Area=0.554 ac 56.77% Impervious Runoff Depth>1.00" Tc=6.0 min CN=88 Runoff=1.04 cfs 0.046 of Subcatchment 1.5: Subcat 1.5 Runoff Area=0.128 ac 93.32% Impervious Runoff Depth>1.61" Tc=6.0 min CN=96 Runoff=0.35 cfs 0.017 of Subcatchment 1.6: Subcat 1.6 Runoff Area=0.182 ac 33.26% Impervious Runoff Depth>0.68" Tc=6.0 min CN=82 Runoff=0.24 cfs 0.010 of Subcatchment2: Subcat 2 Runoff Area=0.249 ac 71.95% Impervious Runoff Depth>1.20" Tc=6.0 min CN=91 Runoff=0.55 cfs 0.025 of Subcatchment2.1: Subcat 2.1 Runoff Area=0.428 ac 56.79% Impervious Runoff Depth>1.00" Tc=6.0 min CN=88 Runoff=0.80 cfs 0.036 of Subcatchment2.10: Subcat 2.10 Runoff Area=0.725 ac 99.80% Impervious Runoff Depth>1.79" Tc=6.0 min CN=98 Runoff=2.11 cfs 0.108 of Subcatchment2.11: Subcat 2.11 Runoff Area=0.087 ac 25.99% Impervious Runoff Depth>0.59" Tc=6.0 min CN=80 Runoff=0.10 cfs 0.004 of Subcatchment2.19: Subcat 2.19 Runoff Area=2.910 ac 29.54% Impervious Runoff Depth>0.54" Flow Length=369' Tc=22.4 min CN=79 Runoff=1.69 cfs 0.132 of Subcatchment2.2: Subcat 2.2 Runoff Area=0.882 ac 99.37% Impervious Runoff Depth>1.79" Tc=6.0 min CN=98 Runoff=2.57 cfs 0.132 of Subcatchment2.4a: Subcat 2.4a Runoff Area=2.326 ac 56.60% Impervious Runoff Depth>0.94" Flow Length=457' Tc=19.4 min CN=87 Runoff=2.67 cfs 0.181 of Subcatchment2.4b: Subcat 2.4b Runoff Area=0.199 ac 54.92% Impervious Runoff Depth>0.94" Tc=6.0 min CN=87 Runoff=0.35 cfs 0.016 of Subcatchment2.4c: Subcat 2.4c Runoff Area=0.505 ac 28.66% Impervious Runoff Depth>0.59" Flow Length=320' Tc=6.2 min CN=80 Runoff=0.56 cfs 0.025 of Subcatchment2.5: Subcat 2.5 Runoff Area=0.188 ac 41.66% Impervious Runoff Depth>0.78" Tc=6.0 min CN=84 Runoff=0.28 cfs 0.012 of Post-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 8 Subcatchment2.6a: Subcat 2.6a Runoff Area=0.193 ac 38.35% Impervious Runoff Depth>0.73" Tc=6.0 min CN=83 Runoff=0.27 cfs 0.012 of Subcatchment2.7: Subcat 2.7 Runoff Area=0.274 ac 99.93% Impervious Runoff Depth>1.79" Tc=6.0 min CN=98 Runoff=0.80 cfs 0.041 of Subcatchmentl Subcat 3 Runoff Area=0.343 ac 85.99% Impervious Runoff Depth>1.52" Tc=6.0 min CN=95 Runoff=0.91 cfs 0.044 of Subcatchment4: Subcat 4 Runoff Area=1.290 ac 34.37% Impervious Runoff Depth>0.63" Flow Length=313' Tc=8.5 min CN=81 Runoff=1.43 cfs 0.068 of Subcatchment5: Subcat 5 Runoff Area=0.448 ac 27.63% Impervious Runoff Depth>0.59" Flow Length=249' Tc=11.8 min CN=80 Runoff=0.40 cfs 0.022 of Subcatchment6: Subcat 6 Runoff Area=0.241 ac 17.44% Impervious Runoff Depth>0.51" Tc=6.0 min CN=78 Runoff=0.23 cfs 0.010 of Subcatchment7: Subcat 7 Runoff Area=0.144 ac 4.83% Impervious Runoff Depth>0.40" Tc=6.0 min CN=75 Runoff=0.11 cfs 0.005 of Subcatchment8: Subcat 8 Runoff Area=0.151 ac 21.63% Impervious Runoff Depth>0.55" Flow Length=133' Tc=6.5 min CN=79 Runoff=0.16 cfs 0.007 of Subcatchment9: Subcat 9 Runoff Area=0.895 ac 53.57% Impervious Runoff Depth>0.94" Tc=6.0 min CN=87 Runoff=1.58 cfs 0.070 of Subcatchment 10: Subcat 10 Runoff Area=0.441 ac 83.28% Impervious Runoff Depth>1.44" Tc=6.0 min CN=94 Runoff=1.12 cfs 0.053 of Subcatchment 11: Subcat 11 Runoff Area=0.412 ac 29.82% Impervious Runoff Depth>0.59" Flow Length=187' Tc=7.1 min CN=80 Runoff=0.45 cfs 0.020 of Subcatchment 12: Subcat 12 Runoff Area=0.262 ac 54.24% Impervious Runoff Depth>0.94" Tc=6.0 min CN=87 Runoff=0.46 cfs 0.021 of Subcatchment69C: Subcat 69C Runoff Area=0.817 ac 25.99% Impervious Runoff Depth>0.51" Flow Length=509' Tc=17.4 min CN=78 Runoff=0.51 cfs 0.034 of SubcatchmentSF1: Subcat SH Runoff Area=3.431 ac 0.34% Impervious Runoff Depth>0.43" Flow Length=400' Tc=21.9 min CN=76 Runoff=1.51 cfs 0.124 of SubcatchmentSF2: Subcat SF2 Runoff Area=1.933 ac 14.73% Impervious Runoff Depth>0.54" Flow Length=502' Tc=20.8 min CN=79 Runoff=1.18 cfs 0.088 of SubcatchmentSF1 Subcat SF3 Runoff Area=0.358 ac 62.50% Impervious Runoff Depth>1.07" Tc=6.0 min CN=89 Runoff=0.71 cfs 0.032 of SubcatchmentSF3a: Subcat SF3a Runoff Area=0.146 ac 99.57% Impervious Runoff Depth>1.79" Tc=6.0 min CN=98 Runoff=0.43 cfs 0.022 of SubcatchmentSF4: Subcat SF4 Runoff Area=1.125 ac 0.00% Impervious Runoff Depth>0.26" Flow Length=340' Slope=0.0800 '/' Tc=16.5 min CN=70 Runoff=0.28 cfs 0.024 of Post-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 9 SubcatchmentSF4a: Subcat SF4a Runoff Area=0.844 ac 21.52% Impervious Runoff Depth>0.51" Flow Length=223' Tc=15.3 min CN=78 Runoff=0.56 cfs 0.036 of SubcatchmentSF5: Subcat SF5 Runoff Area=0.386 ac 80.96% Impervious Runoff Depth>1.36" Tc=6.0 min CN=93 Runoff=0.94 cfs 0.044 of SubcatchmentSF6: Subcat SF6 Runoff Area=0.267 ac 45.37% Impervious Runoff Depth>0.77" Flow Length=139' Tc=9.3 min CN=84 Runoff=0.35 cfs 0.017 of SubcatchmentSF7: Subcat SF7 Runoff Area=0.361 ac 0.68% Impervious Runoff Depth>0.34" Tc=6.0 min CN=73 Runoff=0.22 cfs 0.010 of Reach 2R: Vegetated Swale Avg. Flow Depth=0.26' Max Vel=0.48 fps Inflow=0.81 cfs 0.057 of n=0.150 L=171.0' S=0.0175'/' Capacity=8.33 cfs Outflow=0.72 cfs 0.057 of Reach 4R: Swale Avg. Flow Depth=0.31' Max Vel=0.97 fps Inflow=1.41 cfs 0.071 of n=0.150 L=290.0' S=0.0621 T Capacity=11.04 cfs Outflow=1.21 cfs 0.070 of Reach 5R: Swale Avg. Flow Depth=0.18' Max Vel=0.41 fps Inflow=0.35 cfs 0.017 of n=0.150 L=75.0' S=0.0200'/' Capacity=7.57 cfs Outflow=0.33 cfs 0.017 of Pond 2P: HS TO SWALE Peak Elev=447.49' Inflow=1.20 cfs 0.061 of 15.0" Round Culvert n=0.013 L=25.0' S=0.0080'/' Outflow=1.20 cfs 0.061 of Pond 5P: CB -2 TO CB -1 Peak EIev=450.11' Inflow=0.94 cfs 0.044 of 12.0" Round Culvert n=0.013 L=262.0' S=0.0076'/' Outflow=0.94 cfs 0.044 of Pond 6P: CB -1 TO HS Peak EIev=448.02' Inflow=1.20 cfs 0.061 of 15.0" Round Culvert n=0.013 L=10.0' S=0.0500'/' Outflow=1.20 cfs 0.061 of Pond 7P: YD -1 TO CB -1 Peak Elev=449.31' Inflow=0.33 cfs 0.017 of 12.0" Round Culvert n=0.013 L=182.0' S=0.0077'/' Outflow=0.33 cfs 0.017 of Pond 10P: pipe Peak EIev=470.49' Inflow=0.91 cfs 0.044 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0400 T Outflow=0.91 cfs 0.044 of Pond 19P: pipe Peak Elev=465.55' Inflow=1.12 cfs 0.053 of 12.0" Round Culvert n=0.013 L=155.0' S=0.0194'/' Outflow=1.12 cfs 0.053 of Pond 29P: pipe Peak Elev=461.32' Inflow=0.42 cfs 0.045 of 12.0" Round Culvert n=0.013 L=90.0' S=0.0444'/' Outflow=0.42 cfs 0.045 of Pond 30P: pipe Peak Elev=457.23' Inflow=1.75 cfs 0.139 of 15.0" Round Culvert n=0.013 L=220.0' S=0.0050'/' Outflow=1.75 cfs 0.139 of Pond 201 P: Forebay Peak Elev=423.31' Storage=0.118 of Inflow=16.90 cfs 1.169 of Outflow= 16.22 cfs 1.150 of Pond B1.0: Existing Bioretention Peak Elev=465.85' Storage=0.027 of Inflow=1.34 cfs 0.064 of Outflow=0.42 cfs 0.045 of Post-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 10 Pond B2.0: Existing Bioretention Peak EIev=460.47' Storage=0.041 of Inflow=2.49 cfs 0.121 of Primary=1.35 cfs 0.094 of Secondary=0.00 cfs 0.000 of Outflow=1.35 cfs 0.094 of Pond B3.0: Existing Bioretention Peak EIev=447.70' Storage=0.009 of Inflow=0.27 cfs 0.012 of Outflow=0.01 cfs 0.003 of Pond CB13: CB13 to Expanded Wet Pond Peak Elev=432.53' Inflow=13.31 cfs 0.998 of 24.0" Round Culvert n=0.013 L=234.0' S=0.0336'/' Outflow=13.31 cfs 0.998 of Pond CB5: CB5 to ExCB11 Peak EIev=450.41' Inflow=4.78 cfs 0.243 of 18.0" Round Culvert n=0.013 L=372.0' S=0.0118 '/' Outflow=4.78 cfs 0.243 of Pond CB7: CB7 to YD2 Peak Elev=456.55' Inflow=0.88 cfs 0.047 of 12.0" Round Culvert n=0.013 L=114.0' S=0.0053'/' Outflow=0.88 cfs 0.047 of Pond CBEX2: CBEX2 to CB5 Peak Elev=451.31' Inflow=2.21 cfs 0.112 of 12.0" Round Culvert n=0.013 L=154.0' S=0.0056'/' Outflow=2.21 cfs 0.112 of Pond ExCB1 1: ExCB11 to ExCB14 Peak Elev=446.91' Inflow=6.96 cfs 0.467 of 15.0" Round Culvert n=0.013 L=280.0' S=0.0179'/' Outflow=6.96 cfs 0.467 of Pond ExCB1 4: ExCB14 to CB13 Peak Elev=442.78' Inflow=9.49 cfs 0.598 of 15.0" Round Culvert n=0.013 L=218.0' S=0.0399'/' Outflow=9.49 cfs 0.598 of Pond ExCB1 A: ExCB1 A to ExCB2A Peak Elev=436.79' Inflow=0.34 cfs 0.016 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0145'/' Outflow=0.34 cfs 0.016 of Pond ExCB1 B: ExCB1 B to ExCB2B Peak Elev=457.86' Inflow=1.69 cfs 0.132 of 12.0" Round Culvert n=0.013 L=130.0' S=0.0568'/' Outflow=1.69 cfs 0.132 of Pond ExCB2A: ExCB2A to ExCB3A Peak Elev=434.24' Inflow=1.06 cfs 0.052 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0124'/' Outflow=1.06 cfs 0.052 of Pond ExCB2B: ExCB2B to CB13 Peak EIev=450.23' Inflow=2.17 cfs 0.167 of 15.0" Round Culvert n=0.013 L=392.0' S=0.0466'/' Outflow=2.17 cfs 0.167 of Pond ExCB3A: ExCB3A to ExCB6A Peak Elev=432.61' Inflow=3.42 cfs 0.161 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0926'/' Outflow=3.42 cfs 0.161 of Pond ExCB4A: ExCB4A to ExCB3A Peak Elev=433.98' Inflow=1.39 cfs 0.064 of 12.0" Round Culvert n=0.013 L=73.0' S=0.0267'/' Outflow=1.39 cfs 0.064 of Pond ExCB5A: ExCB5A to ExCB4A Peak EIev=437.09' Inflow=0.35 cfs 0.017 of 12.0" Round Culvert n=0.013 L=133.0' S=0.0259'/' Outflow=0.35 cfs 0.017 of Pond ExCB6A: ExCB6A to Expanded Wet Pond Peak EIev=428.10' Inflow=3.65 cfs 0.171 of 12.0" Round Culvert n=0.013 L=80.0' S=0.0270'/' Outflow=3.65 cfs 0.171 of Pond SMP -1: Bioretention Peak EIev=450.55' Storage=827 cf Inflow=0.72 cfs 0.057 of Primary=0.04 cfs 0.031 of Secondary=0.30 cfs 0.014 of Outflow=0.34 cfs 0.044 of Pond SMP -2: Expanded Wet Pond Peak Elev=423.31' Storage=57.582 cf Inflow=18.50 cfs 1.333 of Primary=1.75 cfs 1.072 of Secondary=0.00 cfs 0.000 of Outflow=1.75 cfs 1.072 of Post-Dev Skidmore Swing Type 11 24 -hr 1 -year Rainfall=2.15" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 11 Pond YD2: YD2 to YD6 Peak Elev=455.85' Inflow=1.11 cfs 0.057 of 12.0" Round Culvert n=0.013 L=176.0' S=0.0176'/' Outflow=1.11 cfs 0.057 of Pond YD6: YD6 to CB5 Peak Elev=452.69' Inflow=1.22 cfs 0.062 of 12.0" Round Culvert n=0.013 L=40.0' S=0.0403'/' Outflow=1.22 cfs 0.062 of Link AP -1: AP -1 Inflow=3.47 cfs 1.295 of Primary=3.47 cfs 1.295 of Total Runoff Area = 25.050 ac Runoff Volume = 1.645 of Average Runoff Depth = 0.79" 61.64% Pervious = 15.441 ac 38.36% Impervious = 9.609 ac Post-Dev Skidmore Swing Type 11 24 -hr 10 -year Rainfall=3.75" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 12 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS, Weighted -CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1.1: Subcat 1.1 Runoff Area=0.275 ac 34.42% Impervious Runoff Depth>1.84" Flow Length=190' Tc=7.2 min CN=82 Runoff=0.92 cfs 0.042 of Subcatchment 1.2: Subcat 1.2 Runoff Area=0.268 ac 89.66% Impervious Runoff Depth>3.07" Tc=6.0 min CN=96 Runoff=1.35 cfs 0.069 of Subcatchment 1.3: Subcat 1.3 Runoff Area=0.384 ac 85.26% Impervious Runoff Depth>2.89" Tc=6.0 min CN=94 Runoff=1.87 cfs 0.092 of Subcatchment 1.4: Subcat 1.4 Runoff Area=0.554 ac 56.77% Impervious Runoff Depth>2.33" Tc=6.0 min CN=88 Runoff=2.32 cfs 0.108 of Subcatchment 1.5: Subcat 1.5 Runoff Area=0.128 ac 93.32% Impervious Runoff Depth>3.07" Tc=6.0 min CN=96 Runoff=0.65 cfs 0.033 of Subcatchment 1.6: Subcat 1.6 Runoff Area=0.182 ac 33.26% Impervious Runoff Depth>1.84" Tc=6.0 min CN=82 Runoff=0.62 cfs 0.028 of Subcatchment2: Subcat 2 Runoff Area=0.249 ac 71.95% Impervious Runoff Depth>2.60" Tc=6.0 min CN=91 Runoff=1.13 cfs 0.054 of S u bcatch me nt 2.1: Subcat 2.1 Runoff Area=0.428 ac 56.79% Impervious Runoff Depth>2.33" Tc=6.0 min CN=88 Runoff=1.79 cfs 0.083 of Subcatchment2.10: Subcat 2.10 Runoff Area=0.725 ac 99.80% Impervious Runoff Depth>3.24" Tc=6.0 min CN=98 Runoff=3.75 cfs 0.196 of Subcatchment2.11: Subcat 2.11 Runoff Area=0.087 ac 25.99% Impervious Runoff Depth>1.69" Tc=6.0 min CN=80 Runoff=0.27 cfs 0.012 of Subcatchment2.19: Subcat 2.19 Runoff Area=2.910 ac 29.54% Impervious Runoff Depth>1.61" Flow Length=369' Tc=22.4 min CN=79 Runoff=5.29 cfs 0.390 of Subcatchment2.2: Subcat 2.2 Runoff Area=0.882 ac 99.37% Impervious Runoff Depth>3.24" Tc=6.0 min CN=98 Runoff=4.56 cfs 0.238 of Subcatchment2.4a: Subcat 2.4a Runoff Area=2.326 ac 56.60% Impervious Runoff Depth>2.23" Flow Length=457' Tc=19.4 min CN=87 Runoff=6.28 cfs 0.433 of Subcatchment2.4b: Subcat 2.4b Runoff Area=0.199 ac 54.92% Impervious Runoff Depth>2.24" Tc=6.0 min CN=87 Runoff=0.81 cfs 0.037 of Subcatchment2.4c: Subcat 2.4c Runoff Area=0.505 ac 28.66% Impervious Runoff Depth>1.69" Flow Length=320' Tc=6.2 min CN=80 Runoff=1.60 cfs 0.071 of Subcatchment2.5: Subcat 2.5 Runoff Area=0.188 ac 41.66% Impervious Runoff Depth>1.99" Tc=6.0 min CN=84 Runoff=0.69 cfs 0.031 of Post-Dev Skidmore Swing Type 11 24 -hr 10 -year Rainfall=3.75" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 13 Subcatchment2.6a: Subcat 2.6a Runoff Area=0.193 ac 38.35% Impervious Runoff Depth>1.91" Tc=6.0 min CN=83 Runoff=0.69 cfs 0.031 of Subcatchment2.7: Subcat 2.7 Runoff Area=0.274 ac 99.93% Impervious Runoff Depth>3.24" Tc=6.0 min CN=98 Runoff=1.42 cfs 0.074 of Subcatchmentl Subcat 3 Runoff Area=0.343 ac 85.99% Impervious Runoff Depth>2.98" Tc=6.0 min CN=95 Runoff=1.70 cfs 0.085 of Subcatchment4: Subcat 4 Runoff Area=1.290 ac 34.37% Impervious Runoff Depth>1.76" Flow Length=313' Tc=8.5 min CN=81 Runoff=3.96 cfs 0.189 of Subcatchment5: Subcat 5 Runoff Area=0.448 ac 27.63% Impervious Runoff Depth>1.69" Flow Length=249' Tc=11.8 min CN=80 Runoff=1.18 cfs 0.063 of Subcatchment6: Subcat 6 Runoff Area=0.241 ac 17.44% Impervious Runoff Depth>1.55" Tc=6.0 min CN=78 Runoff=0.70 cfs 0.031 of Subcatchment7: Subcat 7 Runoff Area=0.144 ac 4.83% Impervious Runoff Depth>1.35" Tc=6.0 min CN=75 Runoff=0.37 cfs 0.016 of Subcatchment8: Subcat 8 Runoff Area=0.151 ac 21.63% Impervious Runoff Depth>1.62" Flow Length=133' Tc=6.5 min CN=79 Runoff=0.46 cfs 0.020 of Subcatchment9: Subcat 9 Runoff Area=0.895 ac 53.57% Impervious Runoff Depth>2.24" Tc=6.0 min CN=87 Runoff=3.63 cfs 0.167 of Subcatchment 10: Subcat 10 Runoff Area=0.441 ac 83.28% Impervious Runoff Depth>2.89" Tc=6.0 min CN=94 Runoff=2.15 cfs 0.106 of Subcatchment 11: Subcat 11 Runoff Area=0.412 ac 29.82% Impervious Runoff Depth>1.69" Flow Length=187' Tc=7.1 min CN=80 Runoff=1.28 cfs 0.058 of Subcatchment 12: Subcat 12 Runoff Area=0.262 ac 54.24% Impervious Runoff Depth>2.24" Tc=6.0 min CN=87 Runoff=1.06 cfs 0.049 of Subcatchment69C: Subcat 69C Runoff Area=0.817 ac 25.99% Impervious Runoff Depth>1.54" Flow Length=509' Tc=17.4 min CN=78 Runoff=1.64 cfs 0.105 of SubcatchmentSF1: Subcat SH Runoff Area=3.431 ac 0.34% Impervious Runoff Depth>1.40" Flow Length=400' Tc=21.9 min CN=76 Runoff=5.49 cfs 0.402 of SubcatchmentSF2: Subcat SF2 Runoff Area=1.933 ac 14.73% Impervious Runoff Depth>1.61" Flow Length=502' Tc=20.8 min CN=79 Runoff=3.66 cfs 0.259 of SubcatchmentSF1 Subcat SF3 Runoff Area=0.358 ac 62.50% Impervious Runoff Depth>2.42" Tc=6.0 min CN=89 Runoff=1.54 cfs 0.072 of SubcatchmentSF3a: Subcat SF3a Runoff Area=0.146 ac 99.57% Impervious Runoff Depth>3.24" Tc=6.0 min CN=98 Runoff=0.75 cfs 0.039 of SubcatchmentSF4: Subcat SF4 Runoff Area=1.125 ac 0.00% Impervious Runoff Depth>1.04" Flow Length=340' Slope=0.0800 '/' Tc=16.5 min CN=70 Runoff=1.53 cfs 0.098 of Post-Dev Skidmore Swing Type 11 24 -hr 10 -year Rainfall=3.75" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 14 SubcatchmentSF4a: Subcat SF4a Runoff Area=0.844 ac 21.52% Impervious Runoff Depth>1.54" Flow Length=223' Tc=15.3 min CN=78 Runoff=1.80 cfs 0.109 of SubcatchmentSF5: Subcat SF5 Runoff Area=0.386 ac 80.96% Impervious Runoff Depth>2.79" Tc=6.0 min CN=93 Runoff=1.84 cfs 0.090 of SubcatchmentSF6: Subcat SF6 Runoff Area=0.267 ac 45.37% Impervious Runoff Depth>1.99" Flow Length=139' Tc=9.3 min CN=84 Runoff=0.89 cfs 0.044 of SubcatchmentSF7: Subcat SF7 Runoff Area=0.361 ac 0.68% Impervious Runoff Depth>1.22" Tc=6.0 min CN=73 Runoff=0.85 cfs 0.037 of Reach 2R: Vegetated Swale Avg. Flow Depth=0.47' Max Vel=0.69 fps Inflow=2.20 cfs 0.148 of n=0.150 L=171.0' S=0.0175'/' Capacity=8.33 cfs Outflow=2.08 cfs 0.147 of Reach 4R: Swale Avg. Flow Depth=0.52' Max Vel=1.29 fps Inflow=3.42 cfs 0.171 of n=0.150 L=290.0' S=0.0621 T Capacity=11.04 cfs Outflow=3.09 cfs 0.170 of Reach 5R: Swale Avg. Flow Depth=0.31' Max Vel=0.56 fps Inflow=0.89 cfs 0.044 of n=0.150 L=75.0' S=0.0200'/' Capacity=7.57 cfs Outflow=0.86 cfs 0.044 of Pond 2P: HS TO SWALE Peak Elev=447.82' Inflow=2.57 cfs 0.134 of 15.0" Round Culvert n=0.013 L=25.0' S=0.0080'/' Outflow=2.57 cfs 0.134 of Pond 5P: CB -2 TO CB -1 Peak EIev=450.36' Inflow=1.84 cfs 0.090 of 12.0" Round Culvert n=0.013 L=262.0' S=0.0076'/' Outflow=1.84 cfs 0.090 of Pond 6P: CB -1 TO HS Peak Elev=448.31' Inflow=2.57 cfs 0.134 of 15.0" Round Culvert n=0.013 L=10.0' S=0.0500'/' Outflow=2.57 cfs 0.134 of Pond 7P: YD -1 TO CB -1 Peak Elev=449.52' Inflow=0.86 cfs 0.044 of 12.0" Round Culvert n=0.013 L=182.0' S=0.0077'/' Outflow=0.86 cfs 0.044 of Pond 10P: pipe Peak EIev=470.71' Inflow=1.70 cfs 0.085 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0400'/' Outflow=1.70 cfs 0.085 of Pond 19P: pipe Peak Elev=493.49' Inflow=2.15 cfs 0.106 of 12.0" Round Culvert n=0.013 L=155.0' S=0.0194'/' Outflow=2.15 cfs 0.106 of Pond 29P: pipe Peak EIev=502.06' Inflow=3.25 cfs 0.120 of 12.0" Round Culvert n=0.013 L=90.0' S=0.0444'/' Outflow=3.25 cfs 0.120 of Pond 30P: pipe Peak EIev=502.07' Inflow=8.42 cfs 0.353 of 15.0" Round Culvert n=0.013 L=220.0' S=0.0050'/' Outflow=8.42 cfs 0.353 of Pond 201 P: Forebay Peak Elev=424.57' Storage=0.213 of Inflow=41.69 cfs 2.780 of Outflow=37.17 cfs 2.700 of Pond B1.0: Existing Bioretention Peak Elev=466.27' Storage=0.044 of Inflow=2.93 cfs 0.143 of Outflow=3.25 cfs 0.120 of Post-Dev Skidmore Swing Type 11 24 -hr 10 -year Rainfall=3.75" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 15 Pond B2.0: Existing Bioretention Peak Elev=493.46' Storage=0.081 of Inflow=6.01 cfs 0.295 of Primary=5.91 cfs 0.233 of Secondary=3.74 cfs 0.033 of Outflow=5.94 cfs 0.266 of Pond B3.0: Existing Bioretention Peak EIev=448.05' Storage=0.017 of Inflow=0.69 cfs 0.031 of Outflow=1.39 cfs 0.022 of Pond CB13: CB13 to Expanded Wet Pond Peak Elev=436.63' Inflow=33.37 cfs 2.408 of 24.0" Round Culvert n=0.013 L=234.0' S=0.0336'/' Outflow=33.37 cfs 2.408 of Pond CB5: CB5 to ExCB11 Peak EIev=499.05' Inflow=10.07 cfs 0.516 of 18.0" Round Culvert n=0.013 L=372.0' S=0.0118'/' Outflow= 10.07 cfs 0.516 of Pond CB7: CB7 to YD2 Peak EIev=499.50' Inflow=2.16 cfs 0.117 of 12.0" Round Culvert n=0.013 L=114.0' S=0.0053'/' Outflow=2.16 cfs 0.117 of Pond CBEX2: CBEX2 to CB5 Peak Elev=499.27' Inflow=4.02 cfs 0.208 of 12.0" Round Culvert n=0.013 L=154.0' S=0.0056'/' Outflow=4.02 cfs 0.208 of Pond ExCB1 1: ExCB11 to ExCB14 Peak Elev=497.33' Inflow=19.92 cfs 1.122 of 15.0" Round Culvert n=0.013 L=280.0' S=0.0179'/' Outflow=19.92 cfs 1.122 of Pond ExCB1 4: ExCB14 to CB13 Peak Elev=475.29' Inflow=24.47 cfs 1.360 of 15.0" Round Culvert n=0.013 L=218.0' S=0.0399'/' Outflow=24.47 cfs 1.360 of Pond ExCB1 A: ExCB1 A to ExCB2A Peak EIev=437.01' Inflow=0.92 cfs 0.042 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0145'/' Outflow=0.92 cfs 0.042 of Pond ExCB1 B: ExCB1 B to ExCB2B Peak EIev=459.60' Inflow=5.29 cfs 0.390 of 12.0" Round Culvert n=0.013 L=130.0' S=0.0568'/' Outflow=5.29 cfs 0.390 of Pond ExCB2A: ExCB2A to ExCB3A Peak EIev=436.06' Inflow=2.24 cfs 0.111 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0124'/' Outflow=2.24 cfs 0.111 of Pond ExCB2B: ExCB2B to CB13 Peak Elev=451.46' Inflow=6.82 cfs 0.495 of 15.0" Round Culvert n=0.013 L=392.0' S=0.0466'/' Outflow=6.82 cfs 0.495 of Pond ExCB3A: ExCB3A to ExCB6A Peak Elev=435.27' Inflow=7.06 cfs 0.344 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0926'/' Outflow=7.06 cfs 0.344 of Pond ExCB4A: ExCB4A to ExCB3A Peak Elev=435.94' Inflow=2.97 cfs 0.140 of 12.0" Round Culvert n=0.013 L=73.0' S=0.0267'/' Outflow=2.97 cfs 0.140 of Pond ExCB5A: ExCB5A to ExCB4A Peak Elev=437.21' Inflow=0.65 cfs 0.033 of 12.0" Round Culvert n=0.013 L=133.0' S=0.0259'/' Outflow=0.65 cfs 0.033 of Pond ExCB6A: ExCB6A to Expanded Wet Pond Peak Elev=431.38' Inflow=7.69 cfs 0.371 of 12.0" Round Culvert n=0.013 L=80.0' S=0.0270 '/' Outflow=7.69 cfs 0.371 of Pond SMP -1: Bioretention Peak EIev=450.67' Storage=1,037 cf Inflow=2.08 cfs 0.147 of Primary=0.04 cfs 0.035 of Secondary=2.01 cfs 0.094 of Outflow=2.06 cfs 0.130 of Pond SMP -2: Expanded Wet Pond Peak Elev=424.57' Storage=82.323 cf Inflow=43.30 cfs 3.200 of Primary=2.64 cfs 1.617 of Secondary=17.38 cfs 0.929 of Outflow=20.02 cfs 2.546 of Post-Dev Skidmore Swing Type 11 24 -hr 10 -year Rainfall=3.75" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 16 Pond YD2: YD2 to YD6 Peak Elev=499.45' Inflow=2.86 cfs 0.148 of 12.0" Round Culvert n=0.013 L=176.0' S=0.0176'/' Outflow=2.86 cfs 0.148 of Pond YD6: YD6 to CB5 Peak Elev=499.25' Inflow=3.22 cfs 0.164 of 12.0" Round Culvert n=0.013 L=40.0' S=0.0403'/' Outflow=3.22 cfs 0.164 of Link AP -1: AP -1 Inflow=26.63 cfs 3.247 of Primary=26.63 cfs 3.247 of Total Runoff Area = 25.050 ac Runoff Volume = 4.062 of Average Runoff Depth = 1.95" 61.64% Pervious = 15.441 ac 38.36% Impervious = 9.609 ac Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 1 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR -20 method, UH=SCS, Weighted -CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment 1.1: Subcat 1.1 Runoff Area=0.275 ac 34.42% Impervious Runoff Depth>3.89" Flow Length=190' Tc=7.2 min CN=82 Runoff=1.87 cfs 0.089 of Subcatchment 1.2: Subcat 1.2 Runoff Area=0.268 ac 89.66% Impervious Runoff Depth>5.30" Tc=6.0 min CN=96 Runoff=2.29 cfs 0.119 of Subcatchment 1.3: Subcat 1.3 Runoff Area=0.384 ac 85.26% Impervious Runoff Depth>5.12" Tc=6.0 min CN=94 Runoff=3.21 cfs 0.164 of Subcatchment 1.4: Subcat 1.4 Runoff Area=0.554 ac 56.77% Impervious Runoff Depth>4.52" Tc=6.0 min CN=88 Runoff=4.31 cfs 0.209 of Subcatchment 1.5: Subcat 1.5 Runoff Area=0.128 ac 93.32% Impervious Runoff Depth>5.30" Tc=6.0 min CN=96 Runoff=1.09 cfs 0.057 of Subcatchment 1.6: Subcat 1.6 Runoff Area=0.182 ac 33.26% Impervious Runoff Depth>3.89" Tc=6.0 min CN=82 Runoff=1.27 cfs 0.059 of Subcatchment2: Subcat 2 Runoff Area=0.249 ac 71.95% Impervious Runoff Depth>4.83" Tc=6.0 min CN=91 Runoff=2.02 cfs 0.100 of Subcatchment2.1: Subcat 2.1 Runoff Area=0.428 ac 56.79% Impervious Runoff Depth>4.52" Tc=6.0 min CN=88 Runoff=3.33 cfs 0.161 of Subcatchment2.10: Subcat 2.10 Runoff Area=0.725 ac 99.80% Impervious Runoff Depth>5.45" Tc=6.0 min CN=98 Runoff=6.23 cfs 0.329 of Subcatchment2.11: Subcat 2.11 Runoff Area=0.087 ac 25.99% Impervious Runoff Depth>3.69" Tc=6.0 min CN=80 Runoff=0.58 cfs 0.027 of Subcatchment2.19: Subcat 2.19 Runoff Area=2.910 ac 29.54% Impervious Runoff Depth>3.57" Flow Length=369' Tc=22.4 min CN=79 Runoff=11.63 cfs 0.865 of Subcatchment2.2: Subcat 2.2 Runoff Area=0.882 ac 99.37% Impervious Runoff Depth>5.45" Tc=6.0 min CN=98 Runoff=7.59 cfs 0.401 of Subcatchment2.4a: Subcat 2.4a Runoff Area=2.326 ac 56.60% Impervious Runoff Depth>4.40" Flow Length=457' Tc=19.4 min CN=87 Runoff=11.99 cfs 0.853 of Subcatchment2.4b: Subcat 2.4b Runoff Area=0.199 ac 54.92% Impervious Runoff Depth>4.41" Tc=6.0 min CN=87 Runoff=1.52 cfs 0.073 of Subcatchment2.4c: Subcat 2.4c Runoff Area=0.505 ac 28.66% Impervious Runoff Depth>3.69" Flow Length=320' Tc=6.2 min CN=80 Runoff=3.34 cfs 0.155 of Subcatchment2.5: Subcat 2.5 Runoff Area=0.188 ac 41.66% Impervious Runoff Depth>4.10" Tc=6.0 min CN=84 Runoff=1.36 cfs 0.064 of Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 3 SubcatchmentSF4a: Subcat SF4a Runoff Area=0.844 ac 21.52% Impervious Runoff Depth>3.48" Flow Length=223' Tc=15.3 min CN=78 Runoff=4.02 cfs 0.245 of SubcatchmentSF5: Subcat SF5 Runoff Area=0.386 ac 80.96% Impervious Runoff Depth>5.03" Tc=6.0 min CN=93 Runoff=3.20 cfs 0.162 of SubcatchmentSF6: Subcat SF6 Runoff Area=0.267 ac 45.37% Impervious Runoff Depth>4.10" Flow Length=139' Tc=9.3 min CN=84 Runoff=1.76 cfs 0.091 of SubcatchmentSF7: Subcat SF7 Runoff Area=0.361 ac 0.68% Impervious Runoff Depth>3.00" Tc=6.0 min CN=73 Runoff=2.02 cfs 0.090 of Reach 2R: Vegetated Swale Avg. Flow Depth=0.72' Max Vel=0.87 fps Inflow=4.69 cfs 0.311 of n=0.150 L=171.0' S=0.0175'/' Capacity=8.33 cfs Outflow=4.51 cfs 0.310 of Reach 4R: Swale Avg. Flow Depth=0.76' Max Vel=1.58 fps Inflow=6.75 cfs 0.343 of n=0.150 L=290.0' S=0.0621 T Capacity=11.04 cfs Outflow=6.28 cfs 0.341 of Reach 5R: Swale Avg. Flow Depth=0.45' Max Vel=0.70 fps Inflow=1.76 cfs 0.091 of n=0.150 L=75.0' S=0.0200'/' Capacity=7.57 cfs Outflow=1.71 cfs 0.091 of Pond 2P: HS TO SWALE Peak Elev=448.31' Inflow=4.72 cfs 0.252 of 15.0" Round Culvert n=0.013 L=25.0' S=0.0080'/' Outflow=4.72 cfs 0.252 of Pond 5P: CB -2 TO CB -1 Peak Elev=450.82' Inflow=3.20 cfs 0.162 of 12.0" Round Culvert n=0.013 L=262.0' S=0.0076'/' Outflow=3.20 cfs 0.162 of Pond 6P: CB -1 TO HS Peak Elev=448.87' Inflow=4.72 cfs 0.252 of 15.0" Round Culvert n=0.013 L=10.0' S=0.0500'/' Outflow=4.72 cfs 0.252 of Pond 7P: YD -1 TO CB -1 Peak Elev=449.85' Inflow=1.71 cfs 0.091 of 12.0" Round Culvert n=0.013 L=182.0' S=0.0077'/' Outflow=1.71 cfs 0.091 of Pond 10P: pipe Peak Elev=743.58' Inflow=2.89 cfs 0.149 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0400'/' Outflow=2.89 cfs 0.149 of Pond 19P: pipe Peak Elev=686.96' Inflow=3.69 cfs 0.188 of 12.0" Round Culvert n=0.013 L=155.0' S=0.0194'/' Outflow=3.69 cfs 0.188 of Pond 29P: pipe Peak Elev=743.52' Inflow=6.54 cfs 0.252 of 12.0" Round Culvert n=0.013 L=90.0' S=0.0444'/' Outflow=6.54 cfs 0.252 of Pond 30P: pipe Peak Elev=743.21' Inflow=20.18 cfs 0.767 of 15.0" Round Culvert n=0.013 L=220.0' S=0.0050'/' Outflow=20.18 cfs 0.767 of Pond 201 P: Forebay Peak Elev=425.46' Storage=0.252 of Inflow=87.63 cfs 5.519 of Outflow=83.04 cfs 5.399 of Pond B1.0: Existing Bioretention Peak Elev=743.57' Storage=0.084 of Inflow=5.51 cfs 0.276 of Outflow=6.54 cfs 0.252 of Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 4 Pond B2.0: Existing Bioretention Peak Elev=686.98' Storage=0.081 of Inflow=11.79 cfs 0.595 of Primary=18.32 cfs 0.515 of Secondary=6.61 cfs 0.049 of Outflow=18.32 cfs 0.565 of Pond B3.0: Existing Bioretention Peak Elev=715.53' Storage=0.021 of Inflow=1.38 cfs 0.064 of Outflow=2.21 cfs 0.055 of Pond CB13: CB13 to Expanded Wet Pond Peak Elev=462.13' Inflow=73.68 cfs 4.823 of 24.0" Round Culvert n=0.013 L=234.0' S=0.0336'/' Outflow=73.68 cfs 4.823 of Pond CB5: CB5 to ExCB11 Peak Elev=721.58' Inflow=18.58 cfs 0.967 of 18.0" Round Culvert n=0.013 L=372.0' S=0.0118'/' Outflow= 18.58 cfs 0.967 of Pond CB7: CB7 to YD2 Peak Elev=723.46' Inflow=4.26 cfs 0.238 of 12.0" Round Culvert n=0.013 L=114.0' S=0.0053'/' Outflow=4.26 cfs 0.238 of Pond CBEX2: CBEX2 to CB5 Peak Elev=722.26' Inflow=6.81 cfs 0.356 of 12.0" Round Culvert n=0.013 L=154.0' S=0.0056'/' Outflow=6.81 cfs 0.356 of Pond ExCB1 1: ExCB11 to ExCB14 Peak Elev=715.45' Inflow=46.28 cfs 2.233 of 15.0" Round Culvert n=0.013 L=280.0' S=0.0179'/' Outflow=46.28 cfs 2.233 of Pond ExCB1 4: ExCB14 to CB13 Peak Elev=637.87' Inflow=53.84 cfs 2.634 of 15.0" Round Culvert n=0.013 L=218.0' S=0.0399'/' Outflow=53.84 cfs 2.634 of Pond ExCB1A: ExCB1Ato ExCB2A Peak Elev=457.39' Inflow=1.87 cfs 0.089 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0145'/' Outflow=1.87 cfs 0.089 of Pond ExCB1 B: ExCB1 B to ExCB2B Peak EIev=500.68' Inflow=11.63 cfs 0.865 of 12.0" Round Culvert n=0.013 L=130.0' S=0.0568'/' Outflow= 11.63 cfs 0.865 of Pond ExCB2A: ExCB2A to ExCB3A Peak Elev=457.25' Inflow=4.10 cfs 0.208 of 12.0" Round Culvert n=0.013 L=186.0' S=0.0124'/' Outflow=4.10 cfs 0.208 of Pond ExCB2B: ExCB2B to CB13 Peak Elev=481.69' Inflow=15.05 cfs 1.102 of 15.0" Round Culvert n=0.013 L=392.0' S=0.0466'/' Outflow= 15.05 cfs 1.102 of Pond ExCB3A: ExCB3A to ExCB6A Peak Elev=455.79' Inflow=12.70 cfs 0.637 of 12.0" Round Culvert n=0.013 L=50.0' S=0.0926'/' Outflow= 12.70 cfs 0.637 of Pond ExCB4A: ExCB4A to ExCB3A Peak Elev=456.86' Inflow=5.40 cfs 0.265 of 12.0" Round Culvert n=0.013 L=73.0' S=0.0267'/' Outflow=5.40 cfs 0.265 of Pond ExCB5A: ExCB5A to ExCB4A Peak Elev=456.88' Inflow=1.09 cfs 0.057 of 12.0" Round Culvert n=0.013 L=133.0' S=0.0259'/' Outflow=1.09 cfs 0.057 of Pond ExCB6A: ExCB6A to Expanded Wet Pond Peak Elev=445.13' Inflow=13.97 cfs 0.696 of 12.0" Round Culvert n=0.013 L=80.0' S=0.0270'/' Outflow= 13.97 cfs 0.696 of Pond SMP -1: Bioretention Peak EIev=450.78' Storage=1,247 cf Inflow=4.51 cfs 0.310 of Primary=0.04 cfs 0.041 of Secondary=4.43 cfs 0.251 of Outflow=4.47 cfs 0.292 of Pond SMP -2: Expanded Wet Pond Peak Elev=425.45' Storage=102.162 cf Inflow=97.94 cfs 6.470 of Primary=2.81 cfs 1.969 of Secondary=70.00 cfs 3.632 of Outflow=72.80 cfs 5.600 of Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 5 Pond YD2: YD2 to YD6 Peak Elev=723.24' Inflow=5.77 cfs 0.308 of 12.0" Round Culvert n=0.013 L=176.0' S=0.0176'/' Outflow=5.77 cfs 0.308 of Pond YD6: YD6 to CB5 Peak Elev=722.42' Inflow=6.61 cfs 0.346 of 12.0" Round Culvert n=0.013 L=40.0' S=0.0403'/' Outflow=6.61 cfs 0.346 of Link AP -1: AP -1 Inflow=94.26 cfs 7.220 of Primary=94.26 cfs 7.220 of Total Runoff Area = 25.050 ac Runoff Volume = 8.294 of Average Runoff Depth = 3.97" 61.64% Pervious = 15.441 ac 38.36% Impervious = 9.609 ac Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 6 Summary for Subcatchment 1.1: Subcat 1.1 Runoff = 1.87 cfs @ 11.98 hrs, Volume= 0.089 af, Depth> 3.89" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.180 74 >75% Grass cover, Good, HSG C 0.095 98 Paved parking, HSG C 0.275 82 Weighted Average 0.180 65.58% Pervious Area 0.095 34.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 67 0.0400 0.19 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 1.2 123 0.0590 1.70 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 7.2 190 Total Summary for Subcatchment 1.2: Subcat 1.2 Runoff = 2.29 cfs @ 11.96 hrs, Volume= 0.119 af, Depth> 5.30" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.028 74 >75% Grass cover, Good, HSG C 0.241 98 Paved parking, HSG C 0.268 96 Weighted Average 0.028 10.34% Pervious Area 0.241 89.66% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 1.3: Subcat 1.3 Runoff = 3.21 cfs @ 11.96 hrs, Volume= 0.164 af, Depth> 5.12" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 7 Area (ac) CN DescriDtion 0.057 74 >75% Grass cover, Good, HSG C 0.327 98 Paved parking, HSG C 0.384 94 Weighted Average 0.057 14.74% Pervious Area 0.327 85.26% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 1.4: Subcat 1.4 Runoff = 4.31 cfs @ 11.96 hrs, Volume= 0.209 af, Depth> 4.52" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.240 74 >75% Grass cover, Good, HSG C 0.315 98 Paved parking, HSG C 0.554 88 Weighted Average 0.240 43.23% Pervious Area 0.315 56.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 1.5: Subcat 1.5 Runoff = 1.09 cfs @ 11.96 hrs, Volume= 0.057 af, Depth> 5.30" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.009 74 >75% Grass cover, Good, HSG C 0.120 98 Paved parking, HSG C 0.128 96 Weighted Average 0.009 6.68% Pervious Area 0.120 93.32% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment 1.6: Subcat 1.6 Runoff = 1.27 cfs @ 11.97 hrs, Volume= 0.059 af, Depth> 3.89" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.121 74 >75% Grass cover, Good, HSG C 0.060 98 Paved parking, HSG C 0.182 82 Weighted Average 0.121 66.74% Pervious Area 0.060 33.26% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2: Subcat 2 Runoff = 2.02 cfs @ 11.96 hrs, Volume= 0.100 af, Depth> 4.83" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.070 74 >75% Grass cover, Good, HSG C 0.179 98 Paved parking, HSG C 0.249 91 Weighted Average 0.070 28.05% Pervious Area 0.179 71.95% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.1: Subcat 2.1 Runoff = 3.33 cfs @ 11.96 hrs, Volume= 0.161 af, Depth> 4.52" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.185 74 >75% Grass cover, Good, HSG C 0.243 98 Paved parking, HSG C 0.428 88 Weighted Average 0.185 43.21 % Pervious Area 0.243 56.79% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 9 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.10: Subcat 2.10 Runoff = 6.23 cfs @ 11.96 hrs, Volume= 0.329 af, Depth> 5.45" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.001 74 >75% Grass cover, Good, HSG C 0.723 98 Paved parking, HSG C 0.725 98 Weighted Average 0.001 0.20% Pervious Area 0.723 99.80% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.11: Subcat 2.11 Runoff = 0.58 cfs @ 11.97 hrs, Volume= 0.027 af, Depth> 3.69" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.064 74 >75% Grass cover, Good, HSG C 0.022 98 Paved parking, HSG C 0.087 80 Weighted Average 0.064 74.01 % Pervious Area 0.022 25.99% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.19: Subcat 2.19 Runoff = 11.63 cfs @ 12.15 hrs, Volume= 0.865 af, Depth> 3.57" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 10 Area (ac) CN DescriDtion 0.596 74 >75% Grass cover, Good, HSG C 0.860 98 Paved parking, HSG C 1.454 70 Woods, Good, HSG C 2.910 79 Weighted Average 2.051 0.09 70.46% Pervious Area 0.860 29.54% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 18.1 100 0.0400 0.09 Sheet Flow, 1.316 56.60% Impervious Area Woods: Light underbrush n= 0.400 P2= 2.60" 4.1 249 0.0400 1.00 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.1 20 0.0300 3.52 Shallow Concentrated Flow, Paved Kv= 20.3 fps 22.4 369 Total Summary for Subcatchment 2.2: Subcat 2.2 Runoff = 7.59 cfs @ 11.96 hrs, Volume= 0.401 af, Depth> 5.45" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.006 74 >75% Grass cover, Good, HSG C 0.877 98 Paved parking, HSG C 0.882 98 Weighted Average 0.006 0.63% Pervious Area 0.877 99.37% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.4a: Subcat 2.4a Runoff = 11.99 cfs @ 12.11 hrs, Volume= 0.853 af, Depth> 4.40" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.685 74 >75% Grass cover, Good, HSG C 1.316 98 Paved parking, HSG C 0.325 70 Woods, Good, HSG C 2.326 87 Weighted Average 1.009 43.40% Pervious Area 1.316 56.60% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 11 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 15.9 100 0.0550 0.10 Sheet Flow, 0.145 28.66% Impervious Area Woods: Light underbrush n= 0.400 P2= 2.60" 2.0 121 0.0400 1.00 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 0.8 93 0.0750 1.92 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 0.7 143 0.0270 3.34 Shallow Concentrated Flow, Paved Kv= 20.3 fps 19.4 457 Total Summary for Subcatchment 2.4b: Subcat 2.4b Runoff = 1.52 cfs @ 11.96 hrs, Volume= 0.073 af, Depth> 4.41" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.090 74 >75% Grass cover, Good, HSG C 0.109 98 Paved parking, HSG C 0.199 87 Weighted Average 0.090 45.08% Pervious Area 0.109 54.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.4c: Subcat 2.4c Runoff = 3.34 cfs @ 11.97 hrs, Volume= 0.155 af, Depth> 3.69" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.250 74 >75% Grass cover, Good, HSG C 0.145 98 Paved parking, HSG C 0.109 70 Woods, Good, HSG C 0.505 80 Weighted Average 0.360 71.34% Pervious Area 0.145 28.66% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 12 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 76 0.0789 0.25 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 1.2 244 0.0492 3.33 Shallow Concentrated Flow, Grassed Waterwav Kv= 15.0 fps 6.2 320 Total Summary for Subcatchment 2.5: Subcat 2.5 Runoff = 1.36 cfs @ 11.97 hrs, Volume= 0.064 af, Depth> 4.10" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.110 74 >75% Grass cover, Good, HSG C 0.078 98 Paved parking, HSG C 0.188 84 Weighted Average 0.110 58.34% Pervious Area 0.078 41.66% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.6a: Subcat 2.6a Runoff = 1.38 cfs @ 11.97 hrs, Volume= 0.064 af, Depth> 4.00" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.119 74 >75% Grass cover, Good, HSG C 0.074 98 Paved parking, HSG C 0.193 83 Weighted Average 0.119 61.65% Pervious Area 0.074 38.35% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 2.7: Subcat 2.7 Runoff = 2.36 cfs @ 11.96 hrs, Volume= 0.125 af, Depth> 5.45" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 13 Area (ac) CN Description 0.000 74 >75% Grass cover, Good, HSG C 0.274 98 Paved parking, HSG C 0.274 98 Weighted Average 0.000 0.07% Pervious Area 0.274 99.93% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 3: Subcat 3 Runoff = 2.89 cfs @ 11.96 hrs, Volume= 0.149 af, Depth> 5.22" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.048 74 >75% Grass cover, Good, HSG C 0.295 98 Paved parking, HSG C 0.343 95 Weighted Average 0.048 14.01 % Pervious Area 0.295 85.99% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 4: Subcat 4 Runoff = 8.25 cfs @ 12.00 hrs, Volume= 0.407 af, Depth> 3.79" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.343 74 >75% Grass cover, Good, HSG C 0.443 98 Paved parking, HSG C 0.503 70 Woods, Good, HSG C 1.290 81 Weighted Average 0.847 65.63% Pervious Area 0.443 34.37% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 14 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.0 100 0.0600 0.24 Sheet Flow, 0.124 2.3 149 27.63% Impervious Area 1.06 Grass: Short n= 0.150 P2= 2.60" 0.2 66 0.0610 5.01 Shallow Concentrated Flow, Paved Kv= 20.3 fps 1.3 147 0.0750 1.92 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 8.5 313 Tota Summary for Subcatchment 5: Subcat 5 Runoff = 2.50 cfs @ 12.03 hrs, Volume= 0.137 af, Depth> 3.68" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.283 74 >75% Grass cover, Good, HSG C 0.124 98 Paved parking, HSG C 0.041 70 Woods, Good, HSG C 0.448 80 Weighted Average 0.324 72.37% Pervious Area 0.124 2.3 149 27.63% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.5 100 0.0280 0.18 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 2.3 149 0.0230 1.06 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 11.8 249 Total Summary for Subcatchment 6: Subcat 6 Runoff = 1.53 cfs @ 11.97 hrs, Volume= 0.070 af, Depth> 3.49" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.199 74 >75% Grass cover, Good, HSG C 0.042 98 Paved parking, HSG C 0.241 78 Weighted Average 0.199 82.56% Pervious Area 0.042 17.44% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 15 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 7: Subcat 7 Runoff = 0.85 cfs @ 11.97 hrs, Volume= 0.038 af, Depth> 3.19" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.137 74 >75% Grass cover, Good, HSG C 0.007 98 Paved parking, HSG C 0.144 75 Weighted Average 0.137 95.17% Pervious Area 0.007 4.83% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 8: Subcat 8 Runoff = 0.98 cfs @ 11.98 hrs, Volume= 0.045 af, Depth> 3.59" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.118 74 >75% Grass cover, Good, HSG C 0.033 98 Paved parking, HSG C 0.151 79 Weighted Average 0.118 78.37% Pervious Area 0.033 21.63% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.2 100 0.0800 0.27 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 0.3 33 0.0910 2.11 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 6.5 133 Total Summary for Subcatchment 9: Subcat 9 Runoff = 6.85 cfs @ 11.96 hrs, Volume= 0.329 af, Depth> 4.41" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 16 Area (ac) CN Description 0.383 74 >75% Grass cover, Good, HSG C 0.479 98 Paved parking, HSG C 0.032 70 Woods, Good, HSG C 0.895 87 Weighted Average 0.416 46.43% Pervious Area 0.479 53.57% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 10: Subcat 10 Runoff = 3.69 cfs @ 11.96 hrs, Volume= 0.188 af, Depth> 5.12" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.074 74 >75% Grass cover, Good, HSG C 0.367 98 Paved parking, HSG C 0.441 94 Weighted Average 0.074 16.72% Pervious Area 0.367 83.28% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 11: Subcat 11 Runoff = 2.69 cfs @ 11.98 hrs, Volume= 0.127 af, Depth> 3.69" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.149 74 >75% Grass cover, Good, HSG C 0.123 98 Paved parking, HSG C 0.141 70 Woods, Good, HSG C 0.412 80 Weighted Average 0.289 70.18% Pervious Area 0.123 29.82% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 17 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 100 0.0900 0.28 Sheet Flow, 0.604 74.01 % Pervious Area Grass: Short n= 0.150 P2= 2.60" 1.1 87 0.0340 1.29 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 7.1 187 Total Summary for Subcatchment 12: Subcat 12 Runoff = 2.00 cfs @ 11.96 hrs, Volume= 0.096 af, Depth> 4.41" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.120 74 >75% Grass cover, Good, HSG C 0.142 98 Paved parking, HSG C 0.262 87 Weighted Average 0.120 45.76% Pervious Area 0.142 54.24% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment 69C: Subcat 69C Runoff = 3.66 cfs @ 12.10 hrs, Volume= 0.237 af, Depth> 3.48" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.073 74 >75% Grass cover, Good, HSG C 0.212 98 Paved parking, HSG C 0.531 70 Woods, Good, HSG C 0.817 78 Weighted Average 0.604 74.01 % Pervious Area 0.212 25.99% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 18 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 12.5 100 0.1000 0.13 Sheet Flow, 2.477 77 Woods, Good, HSG D 3.431 Woods: Light underbrush n= 0.400 P2= 2.60" 3.7 273 0.0590 1.21 Shallow Concentrated Flow, 0.34% Impervious Area Woodland Kv= 5.0 fps 0.1 23 0.0200 2.87 Shallow Concentrated Flow, Paved Kv= 20.3 fps 1.1 113 0.0640 1.77 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 17.4 509 Total Summary for Subcatchment SH: Subcat SH Runoff = 12.82 cfs @ 12.15 hrs, Volume= 0.936 af, Depth> 3.27" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.121 74 >75% Grass cover, Good, HSG C 0.136 80 >75% Grass cover, Good, HSG D 0.001 98 Paved parking, HSG C 0.011 98 Paved parking, HSG D 0.684 70 Woods, Good, HSG C 2.477 77 Woods, Good, HSG D 3.431 76 Weighted Average 3.419 99.66% Pervious Area 0.012 0.34% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 18.1 100 0.0400 0.09 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 2.60" 3.8 300 0.0680 1.30 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 21.9 400 Total Summary for Subcatchment SF2: Subcat SF2 Runoff = 8.05 cfs @ 12.13 hrs, Volume= 0.575 af, Depth> 3.57" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type 11 24 -hr 100 -year Rainfall=6.20" Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 20 Area (ac) CN DescriDtion 0.001 74 >75% Grass cover, Good, HSG C 0.145 98 Paved parking, HSG C 0.146 98 Weighted Average 0.001 0.43% Pervious Area 0.145 99.57% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment SF4: Subcat SF4 Runoff = 4.08 cfs @ 12.09 hrs, Volume= 0.254 af, Depth> 2.71" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.029 74 >75% Grass cover, Good, HSG C 1.079 70 Woods, Good, HSG C 0.017 77 Woods, Good, HSG D 1.125 70 Weighted Average 1.125 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 13.7 100 0.0800 0.12 Sheet Flow, 0.663 78.48% Pervious Area Woods: Light underbrush n= 0.400 P2= 2.60" 2.8 240 0.0800 1.41 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 16.5 340 Total Summary for Subcatchment SF4a: Subcat SF4a Runoff = 4.02 cfs @ 12.07 hrs, Volume= 0.245 af, Depth> 3.48" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.459 74 >75% Grass cover, Good, HSG C 0.182 98 Paved parking, HSG C 0.203 70 Woods, Good, HSG C 0.844 78 Weighted Average 0.663 78.48% Pervious Area 0.182 21.52% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 21 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.4 100 0.0700 0.12 Sheet Flow, 0.146 54.63% Pervious Area Woods: Light underbrush n= 0.400 P2= 2.60" 0.9 123 0.1000 2.21 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 15.3 223 Total Summary for Subcatchment SFS: Subcat SF5 Runoff = 3.20 cfs @ 11.96 hrs, Volume= 0.162 af, Depth> 5.03" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.073 74 >75% Grass cover, Good, HSG C 0.312 98 Paved parking, HSG C 0.386 93 Weighted Average 0.073 19.04% Pervious Area 0.312 80.96% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Subcatchment SF6: Subcat SF6 Runoff = 1.76 cfs @ 12.00 hrs, Volume= 0.091 af, Depth> 4.10" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.101 74 >75% Grass cover, Good, HSG C 0.121 98 Paved parking, HSG C 0.044 70 Woods, Good, HSG C 0.267 84 Weighted Average 0.146 54.63% Pervious Area 0.121 45.37% Impervious Area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 22 Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 0.1 5 0.0200 0.68 Sheet Flow, 0.361 73 Weighted Average 0.358 Smooth surfaces n= 0.011 P2= 2.60" 7.2 56 0.1250 0.13 Sheet Flow, Slope Velocity Capacity Description (min) (feet) Woods: Light underbrush n= 0.400 P2= 2.60" 1.1 25 0.3500 0.37 Sheet Flow, Grass: Short n= 0.150 P2= 2.60" 0.9 53 0.0190 0.96 Shallow Concentrated Flow, Short Grass Pasture Kv= 7.0 fps 9.3 139 Total Summary for Subcatchment SF7: Subcat SF7 Runoff = 2.02 cfs @ 11.97 hrs, Volume= 0.090 af, Depth> 3.00" Runoff by SCS TR -20 method, UH=SCS, Weighted -CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Type II 24 -hr 100 -year Rainfall=6.20" Area (ac) CN Description 0.085 74 >75% Grass cover, Good, HSG C 0.023 80 >75% Grass cover, Good, HSG D 0.002 98 Paved parking, HSG C 0.180 70 Woods, Good, HSG C 0.070 77 Woods, Good, HSG D 0.361 73 Weighted Average 0.358 99.32% Pervious Area 0.002 0.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Summary for Reach 2R: Vegetated Swale Inflow Area = 0.990 ac, 33.03% Impervious, Inflow Depth > 3.77" for 100 -year event Inflow = 4.69 cfs @ 12.04 hrs, Volume= 0.311 of Outflow = 4.51 cfs @ 12.08 hrs, Volume= 0.31Oaf, Atten= 4%, Lag= 2.4 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 0.87 fps, Min. Travel Time= 3.3 min Avg. Velocity = 0.26 fps, Avg. Travel Time= 11.1 min Peak Storage= 886 cf @ 12.08 hrs Average Depth at Peak Storage= 0.72' Bank -Full Depth= 1.00' Flow Area= 8.0 sf, Capacity= 8.33 cfs 5.00' x 1.00' deep channel, n= 0.150 Side Slope Z -value= 3.07' Top Width= 11.00' Length= 171.0' Slope= 0.01757' Inlet Invert= 453.00', Outlet Invert= 450.00' Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 23 Summary for Reach 4R: Swale Inflow Area = 1.013 ac, 43.01 % Impervious, Inflow Depth > 4.06" for 100 -year event Inflow = 6.75 cfs @ 11.98 hrs, Volume= 0.343 of Outflow = 6.28 cfs @ 12.01 hrs, Volume= 0.341 af, Atten= 7%, Lag= 1.9 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 1.58 fps, Min. Travel Time= 3.1 min Avg. Velocity = 0.47 fps, Avg. Travel Time= 10.3 min Peak Storage= 1,154 cf @ 12.01 hrs Average Depth at Peak Storage= 0.76' Bank -Full Depth= 1.00' Flow Area= 6.0 sf, Capacity= 11.04 cfs 3.00' x 1.00' deep channel, n= 0.150 Side Slope Z -value= 3.07' Top Width= 9.00' Length= 290.0' Slope= 0.0621 T Inlet Invert= 444.00', Outlet Invert= 426.00' Inflow Area = I nflow = Outflow = Summary for Reach 5R: Swale 0.267 ac, 45.37% Impervious, Inflow Depth > 4.10" for 100 -year event 1.76 cfs @ 12.00 hrs, Volume= 0.091 of 1.71 cfs @ 12.03 hrs, Volume= 0.091 af, Atten= 3%, Lag= 1.3 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Max. Velocity= 0.70 fps, Min. Travel Time= 1.8 min Avg. Velocity = 0.18 fps, Avg. Travel Time= 6.8 min Peak Storage= 183 cf @ 12.03 hrs Average Depth at Peak Storage= 0.45' Bank -Full Depth= 1.00' Flow Area= 7.0 sf, Capacity= 7.57 cfs 4.00' x 1.00' deep channel, n= 0.150 Side Slope Z -value= 3.07' Top Width= 10.00' Length= 75.0' Slope= 0.02007' Inlet Invert= 453.00', Outlet Invert= 451.50' Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 24 Summary for Pond 2P: HS TO SWALE Inflow Area = 0.653 ac, 66.40% Impervious, Inflow = 4.72 cfs @ 11.98 hrs, Volume Outflow = 4.72 cfs @ 11.98 hrs, Volume Primary = 4.72 cfs @ 11.98 hrs, Volume Inflow Depth > 4.64" = 0.252 of = 0.252 af, = 0.252 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 448.31' @ 11.98 hrs Device Routing Invert Outlet Devices #1 Primary 446.90' 15.0" Round Culvert L= 25.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 446.90'/446.70' S=0.0080'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Primary OutFlow Max=4.58 cfs @ 11.98 hrs HW=448.27' TW=444.73' (Dynamic Tailwater) Ll =Culvert (Barrel Controls 4.58 cfs @ 4.24 fps) Summary for Pond 5P: CB -2 TO CB -1 Inflow Area = 0.386 ac, 80.96% Impervious, Inflow = 3.20 cfs @ 11.96 hrs, Volume Outflow = 3.20 cfs @ 11.96 hrs, Volume Primary = 3.20 cfs @ 11.96 hrs, Volume Inflow Depth > 5.03" = 0.162 of = 0.162 af, = 0.162 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 450.82' @ 11.97 hrs Device Routing Invert Outlet Devices #1 Primary 449.60' 12.0" Round Culvert L= 262.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 449.60'/447.60' S=0.0076'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=3.01 cfs @ 11.96 hrs HW=450.79' TW=448.74' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 3.01 cfs @ 4.07 fps) Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 25 Summary for Pond 6P: CB -1 TO HS Inflow Area = 0.653 ac, 66.40% Impervious, Inflow = 4.72 cfs @ 11.98 hrs, Volume Outflow = 4.72 cfs @ 11.98 hrs, Volume Primary = 4.72 cfs @ 11.98 hrs, Volume Inflow Depth > 4.64" = 0.252 of = 0.252 af, = 0.252 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 448.87' @ 12.00 hrs Device Routing Invert Outlet Devices #1 Primary 447.50' 15.0" Round Culvert L= 10.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 447.50'/ 447.00' S= 0.0500 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Primary OutFlow Max=4.29 cfs @ 11.98 hrs HW=448.80' TW=448.27' (Dynamic Tailwater) Ll =Culvert (Inlet Controls 4.29 cfs @ 3.49 fps) Summary for Pond 7P: YD -1 TO CB -1 Inflow Area = 0.267 ac, 45.37% Impervious, Inflow = 1.71 cfs @ 12.03 hrs, Volume Outflow = 1.71 cfs @ 12.03 hrs, Volume Primary = 1.71 cfs @ 12.03 hrs, Volume Inflow Depth > 4.09" = 0.091 of = 0.091 af, = 0.091 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 449.85' @ 12.04 hrs Device Routing Invert Outlet Devices #1 Primary 449.00' 12.0" Round Culvert L= 182.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 449.00'/447.60' S=0.0077'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=1.68 cfs @ 12.03 hrs HW=449.83' TW=448.76' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 1.68 cfs @ 3.28 fps) Summary for Pond 10P: pipe Inflow Area = 0.343 ac, 85.99% Impervious, Inflow = 2.89 cfs @ 11.96 hrs, Volume Outflow = 2.89 cfs @ 11.96 hrs, Volume Primary = 2.89 cfs @ 11.96 hrs, Volume Inflow Depth > 5.22" = 0.149 of = 0.149 af, = 0.149 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 743.58' @ 12.20 hrs Device Routing Invert Outlet Devices #1 Primary 470.00' 12.0" Round Culvert L= 50.0' CPP, square edge headwall, Ke= 0.500 Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 26 Inlet/ Outlet Invert= 470.00'/468.00' S=0.0400'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=2.83 cfs @ 11.96 hrs HW=471.06' TW=466.53' (Dynamic Tailwater) Ll =Culvert (Inlet Controls 2.83 cfs @ 3.60 fps) Summary for Pond 19P: pipe Inflow Area = 0.441 ac, 83.28% Impervious, Inflow = 3.69 cfs @ 11.96 hrs, Volume Outflow = 3.69 cfs @ 11.96 hrs, Volume Primary = 3.69 cfs @ 11.96 hrs, Volume Inflow Depth > 5.12" = 0.188 of = 0.188 af, = 0.188 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 686.96' @ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 465.00' 12.0" Round Culvert L= 155.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 465.00'/462.00' S=0.0194'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.96 hrs HW=477.02' TW=518.46' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond 29P: pipe Inflow Area = 0.755 ac, 55.31 % Impervious, Inflow = 6.54 cfs @ 12.37 hrs, Volume Outflow = 6.54 cfs @ 12.37 hrs, Volume Primary = 6.54 cfs @ 12.37 hrs, Volume Inflow Depth > 4.01" = 0.252 of = 0.252 af, = 0.252 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 743.52' @ 12.10 hrs Device Routing Invert Outlet Devices #1 Primary 461.00' 12.0" Round Culvert L= 90.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 461.00'/457.00' S=0.0444'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=5.45 cfs @ 12.37 hrs HW=464.59' TW=461.35' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 5.45 cfs @ 6.94 fps) Summary for Pond 30P: pipe Inflow Area = 2.486 ac, 49.40% Impervious, Inflow Depth > 3.70" Inflow = 20.18 cfs @ 12.05 hrs, Volume= 0.767 of Outflow = 20.18 cfs @ 12.05 hrs, Volume= 0.767 af, Primary = 20.18 cfs @ 12.05 hrs, Volume= 0.767 of for 100 -year event Atten= 0%, Lag= 0.0 min Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 27 Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 743.21' @ 12.05 hrs Device Routing Invert Outlet Devices #1 Primary 456.50' 15.0" Round Culvert L= 220.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 456.50'/455.40' S=0.0050'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Primary OutFlow Max=29.60 cfs @ 12.05 hrs HW=740.69' TW=680.82' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 29.60 cfs @ 24.12 fps) Summary for Pond 201 P: Forebay Inflow Area = 15.695 ac, 52.12% Impervious, Inflow Depth > 4.22" for 100 -year event Inflow = 87.63 cfs @ 11.96 hrs, Volume= 5.519 of Outflow = 83.04 cfs @ 12.04 hrs, Volume= 5.399 af, Atten= 5%, Lag= 4.6 min Primary = 83.04 cfs @ 12.04 hrs, Volume= 5.399 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Starting Elev= 422.00' Surf.Area= 0.043 ac Storage= 0.049 of Peak Elev= 425.46' @ 12.14 hrs Surf.Area= 0.096 ac Storage= 0.252 of (0.203 of above start) Plug -Flow detention time= 19.3 min calculated for 5.332 of (97% of inflow) Center -of -Mass det. time= 3.2 min ( 766.3 - 763.1 ) Volume Invert Avail.Storage Storage Description #1 419.00' 0.252 of Custom Stage Data (Irregular)Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (acres) (feet) (acre-feet) (acre-feet) (acres) 419.00 0.002 35.0 0.000 0.000 0.002 420.00 0.009 77.0 0.005 0.005 0.011 421.00 0.019 107.0 0.014 0.019 0.021 422.00 0.043 158.0 0.030 0.049 0.046 423.00 0.058 182.0 0.050 0.099 0.061 424.00 0.076 207.0 0.067 0.166 0.080 425.00 0.096 232.0 0.086 0.252 0.100 Device Routing Invert Outlet Devices #1 Primary 422.00' 25.0' long x 8.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef. (English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64 2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74 Primary OutFlow Max=0.00 cfs @ 12.04 hrs HW=425.18' TW=425.37' (Dynamic Tailwater) Ll =Broad -Crested Rectangular Weir( Controls 0.00 cfs) Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 28 Summary for Pond B1.0: Existing Bioretention Inflow Area = 0.755 ac, 55.31 % Impervious, Inflow = 5.51 cfs @ 11.97 hrs, Volume Outflow = 6.54 cfs @ 12.37 hrs, Volume Primary = 6.54 cfs @ 12.37 hrs, Volume Inflow Depth > 4.38" = 0.276 of = 0.252 af, = 0.252 of for 100 -year event Atten= 0%, Lag= 23.6 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 743.57' @ 12.15 hrs Surf.Area= 0.064 ac Storage= 0.084 of Plug -Flow detention time= 54.0 min calculated for 0.252 of (91 % of inflow) Center -of -Mass det. time= 23.0 min (776.0 - 753.0 ) Volume Invert Avail.Storage Storage Description #1 465.00' 0.084 of Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) 465.00 0.026 0.000 0.000 466.00 0.039 0.032 0.032 467.00 0.064 0.051 0.084 Device Routing Invert Outlet Devices #1 Primary 465.00' 1.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 465.75' 15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Primary OutFlow Max=5.81 cfs @ 12.37 hrs HW=466.70' TW=464.59' (Dynamic Tailwater) �1=Exfiltration (Exfiltration Controls 0.06 cfs) 2=Orifice/Grate (Orifice Controls 5.75 cfs @ 4.69 fps) Summary for Pond B2.0: Existing Bioretention Inflow Area = 1.731 ac, 46.82% Impervious, Inflow = 11.79 cfs @ 11.99 hrs, Volume Outflow = 18.32 cfs @ 11.95 hrs, Volume Primary = 18.32 cfs @ 11.95 hrs, Volume Secondary = 6.61 cfs @ 12.15 hrs, Volume Inflow Depth > 4.13" = 0.595 of = 0.565 af, = 0.515 of = 0.049 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 686.98' @ 12.04 hrs Surf.Area= 0.087 ac Storage= 0.081 of Plug -Flow detention time= 35.9 min calculated for 0.565 of (95% of inflow) Center -of -Mass det. time= 16.0 min (777.3 - 761.3 ) Volume Invert Avail.Storage Storage Description #1 459.50' 0.081 of Custom Stage Data (Prismatic)Listed below (Recalc) Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 29 Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) 459.50 0.029 0.000 0.000 460.00 0.040 0.017 0.017 461.00 0.087 0.063 0.081 Device Routing Invert Outlet Devices #1 Primary 459.50' 1.000 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 460.25' 15.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Secondary 460.75' 20.0' long x 1.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 3.32 Primary OutFlow Max=0.09 cfs @ 11.95 hrs HW=510.34' TW=559.81' (Dynamic Tailwater) � 1=Exfiltration (Exfiltration Controls 0.09 cfs) 2=Orifice/Grate (Controls 0.00 cfs) Secondary OutFlow Max=85,402.44 cfs @ 12.15 hrs HW=582.41' TW=487.73' (Dynamic Tailwater) L3=B road -Crested Rectangular Weir (Weir Controls 85,402.44 cfs @ 35.10 fps) Summary for Pond B3.0: Existing Bioretention Inflow Area = 0.193 ac, 38.35% Impervious, Inflow = 1.38 cfs @ 11.97 hrs, Volume Outflow = 2.21 cfs @ 12.55 hrs, Volume Primary = 2.21 cfs @ 12.55 hrs, Volume Inflow Depth > 4.00" for 100 -year event = 0.064 of = 0.055 af, Atten= 0%, Lag= 35.2 min = 0.055 of Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 715.53' @ 12.05 hrs Surf.Area= 0.030 ac Storage= 0.021 of Plug -Flow detention time= 78.1 min calculated for 0.055 of (86% of inflow) Center -of -Mass det. time= 35.6 min (801.0 - 765.4 ) Volume Invert Avail.Storage Storage Description #1 447.20' 0.021 of Custom Stage Data (Irregular)Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (acres) (feet) (acre-feet) (acre-feet) (acres) 447.20 0.014 102.0 0.000 0.000 0.014 448.20 0.030 152.0 0.021 0.021 0.037 Device Routing Invert Outlet Devices #1 Primary 445.45' 12.0" Round Culvert L= 75.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 445.45'/444.95' S=0.0067'/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf #2 Device 1 447.45' 1.000 in/hr Exfiltration over Surface area above 447.45' Excluded Surface area = 0.017 ac #3 Device 1 447.70' 12.0" Horiz. Yard Drain C= 0.600 Limited to weir flow at low heads Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 30 Primary OutFlow Max=2.05 cfs @ 12.55 hrs HW=448.04' TW=446.73' (Dynamic Tailwater) Ll =Culvert (Passes 2.05 cfs of 3.68 cfs potential flow) � 2=Exfiltration (Exfiltration Controls 0.01 cfs) 3=Yard Drain (Weir Controls 2.04 cfs @ 1.91 fps) Summary for Pond CB13: CB13 to Expanded Wet Pond Inflow Area = 13.904 ac, 50.52% Impervious, Inflow = 73.68 cfs @ 11.96 hrs, Volume Outflow = 73.68 cfs @ 11.96 hrs, Volume Primary = 73.68 cfs @ 11.96 hrs, Volume Inflow Depth > 4.16" = 4.823 of = 4.823 af, = 4.823 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 462.13' @ 11.96 hrs Device Routing Invert Outlet Devices #1 Primary 430.76' 24.0" Round Culvert L= 234.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 430.76'/ 422.90' S= 0.0336 T Cc= 0.900 n= 0.013, Flow Area= 3.14 sf Primary OutFlow Max=70.46 cfs @ 11.96 hrs HW=459.39' TW=424.67' (Dynamic Tailwater) Ll =Culvert (Barrel Controls 70.46 cfs @ 22.43 fps) Summary for Pond CB5: CB5 to ExCB11 Inflow Area = 2.580 ac, 59.95% Impervious, Inflow = 18.58 cfs @ 11.97 hrs, Volume Outflow = 18.58 cfs @ 11.97 hrs, Volume Primary = 18.58 cfs @ 11.97 hrs, Volume Inflow Depth > 4.50" = 0.967 of = 0.967 af, = 0.967 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 721.58' @ 12.05 hrs Device Routing Invert Outlet Devices #1 Primary 449.34' 18.0" Round Culvert L= 372.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 449.34'/444.95' S=0.0118'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf Primary OutFlow Max=0.00 cfs @ 11.97 hrs HW=600.98' TW=691.32' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond CB7: CB7 to YD2 Inflow Area = 0.697 ac, 43.48% Impervious, Inflow Depth > 4.09" Inflow = 4.26 cfs @ 11.99 hrs, Volume= 0.238 of Outflow = 4.26 cfs @ 11.99 hrs, Volume= 0.238 af, Primary = 4.26 cfs @ 11.99 hrs, Volume= 0.238 of for 100 -year event Atten= 0%, Lag= 0.0 min Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 31 Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 723.46' @ 12.20 hrs Device Routing Invert Outlet Devices #1 Primary 456.00' 12.0" Round Culvert L= 114.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 456.00'/455.40' S=0.0053'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.99 hrs HW=479.78' TW=509.92' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond CBEX2: CBEX2 to CB5 Inflow Area = 0.811 ac, 91.92% Impervious, Inflow = 6.81 cfs @ 11.96 hrs, Volume Outflow = 6.81 cfs @ 11.96 hrs, Volume Primary = 6.81 cfs @ 11.96 hrs, Volume Inflow Depth > 5.26" = 0.356 of = 0.356 af, = 0.356 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 722.26' @ 12.10 hrs Device Routing Invert Outlet Devices #1 Primary 450.30' 12.0" Round Culvert L= 154.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 450.30'/449.44' S=0.0056'/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.96 hrs HW=521.58' TW=577.69' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB11: ExCB11 to ExCB14 Inflow Area = 6.342 ac, 53.71 % Impervious, Inflow = 46.28 cfs @ 11.95 hrs, Volume Outflow = 46.28 cfs @ 11.95 hrs, Volume Primary = 46.28 cfs @ 11.95 hrs, Volume Inflow Depth > 4.23" = 2.233 of = 2.233 af, = 2.233 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 715.45' @ 12.00 hrs Device Routing Invert Outlet Devices #1 Primary 444.90' 15.0" Round Culvert L= 280.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 444.90'/439.90' S=0.0179'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Primary OutFlow Max=24.67 cfs @ 11.95 hrs HW=678.93' TW=628.56' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 24.67 cfs @ 20.10 fps) Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 32 Summary for Pond ExCB14: ExCB14 to CB13 Inflow Area = 7.224 ac, 59.29% Impervious, Inflow = 53.84 cfs @ 11.96 hrs, Volume Outflow = 53.84 cfs @ 11.96 hrs, Volume Primary = 53.84 cfs @ 11.96 hrs, Volume Inflow Depth > 4.37" = 2.634 of = 2.634 af, = 2.634 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 637.87' @ 11.96 hrs Device Routing Invert Outlet Devices #1 Primary 439.60' 15.0" Round Culvert L= 218.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 439.60'/ 430.90' S= 0.0399 T Cc= 0.900 n= 0.013, Flow Area= 1.23 sf Primary OutFlow Max=49.66 cfs @ 11.96 hrs HW=628.03' TW=460.61' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 49.66 cfs @ 40.47 fps) Summary for Pond ExCB1A: ExCB1A to ExCB2A Inflow Area = 0.275 ac, 34.42% Impervious, Inflow = 1.87 cfs @ 11.98 hrs, Volume Outflow = 1.87 cfs @ 11.98 hrs, Volume Primary = 1.87 cfs @ 11.98 hrs, Volume Inflow Depth > 3.89" = 0.089 of = 0.089 af, = 0.089 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 457.39' @ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 436.50' 12.0" Round Culvert L= 186.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.50'/433.80' S=0.0145'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.98 hrs HW=441.29' TW=449.12' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB1B: ExCB1B to ExCB2B Inflow Area = 2.910 ac, 29.54% Impervious, Inflow = 11.63 cfs @ 12.15 hrs, Volume Outflow = 11.63 cfs @ 12.15 hrs, Volume Primary = 11.63 cfs @ 12.15 hrs, Volume Inflow Depth > 3.57" = 0.865 of = 0.865 af, = 0.865 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 500.68' @ 12.15 hrs Device Routing Invert Outlet Devices #1 Primary 457.15' 12.0" Round Culvert L= 130.0' CPP, square edge headwall, Ke= 0.500 Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 33 Inlet/ Outlet Invert= 457.15'/449.76' S=0.0568'/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=15.94 cfs @ 12.15 hrs HW=499.63' TW=463.91' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 15.94 cfs @ 20.30 fps) Summary for Pond ExCB2A: ExCB2A to ExCB3A Inflow Area = 0.543 ac, 61.71 % Impervious, Inflow = 4.10 cfs @ 11.97 hrs, Volume Outflow = 4.10 cfs @ 11.97 hrs, Volume Primary = 4.10 cfs @ 11.97 hrs, Volume Inflow Depth > 4.59" = 0.208 of = 0.208 af, = 0.208 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 457.25' @ 12.04 hrs Device Routing Invert Outlet Devices #1 Primary 433.70' 12.0" Round Culvert L= 186.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 433.70'/431.40' S=0.0124'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.97 hrs HW=446.81' TW=452.29' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB2B: ExCB2B to CB13 Inflow Area = 3.727 ac, 28.76% Impervious, Inflow = 15.05 cfs @ 12.14 hrs, Volume Outflow = 15.05 cfs @ 12.14 hrs, Volume Primary = 15.05 cfs @ 12.14 hrs, Volume Inflow Depth > 3.55" = 1.102 of = 1.102 af, = 1.102 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 481.69' @ 12.10 hrs Device Routing Invert Outlet Devices #1 Primary 449.50' 15.0" Round Culvert L= 392.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 449.50'/431.24' S=0.0466'/' Cc= 0.900 n= 0.013, Flow Area= 1.23 sf Primary OutFlow Max=16.25 cfs @ 12.14 hrs HW=468.77' TW=439.78' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 16.25 cfs @ 13.25 fps) Summary for Pond ExCB3A: ExCB3A to ExCB6A Inflow Area = 1.610 ac, 68.15% Impervious, Inflow Depth > 4.75" Inflow = 12.70 cfs @ 11.97 hrs, Volume= 0.637 of Outflow = 12.70 cfs @ 11.97 hrs, Volume= 0.637 af, Primary = 12.70 cfs @ 11.97 hrs, Volume= 0.637 of for 100 -year event Atten= 0%, Lag= 0.0 min Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 34 Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 455.79' @ 12.00 hrs Device Routing Invert Outlet Devices #1 Primary 431.30' 12.0" Round Culvert L= 50.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 431.30'/ 426.67' S= 0.0926 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=9.79 cfs @ 11.97 hrs HW=451.57' TW=444.16' (Dynamic Tailwater) Ll =Culvert (Outlet Controls 9.79 cfs @ 12.46 fps) Summary for Pond ExCB4A: ExCB4A to ExCB3A Inflow Area = 0.683 ac, 63.65% Impervious, Inflow = 5.40 cfs @ 11.96 hrs, Volume Outflow = 5.40 cfs @ 11.96 hrs, Volume Primary = 5.40 cfs @ 11.96 hrs, Volume Inflow Depth > 4.67" = 0.265 of = 0.265 af, = 0.265 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 456.86' @ 12.04 hrs Device Routing Invert Outlet Devices #1 Primary 433.35' 12.0" Round Culvert L= 73.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 433.35'/431.40' S=0.0267'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.96 hrs HW=444.94' TW=451.34' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond ExCB5A: ExCB5A to ExCB4A Inflow Area = 0.128 ac, 93.32% Impervious, Inflow = 1.09 cfs @ 11.96 hrs, Volume Outflow = 1.09 cfs @ 11.96 hrs, Volume Primary = 1.09 cfs @ 11.96 hrs, Volume Inflow Depth > 5.30" = 0.057 of = 0.057 af, = 0.057 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 456.88' @ 12.09 hrs Device Routing Invert Outlet Devices #1 Primary 436.80' 12.0" Round Culvert L= 133.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 436.80'/433.35' S=0.0259'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.96 hrs HW=438.72' TW=444.55' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 35 Summary for Pond ExCB6A: ExCB6A to Expanded Wet Pond Inflow Area = 1.791 ac, 64.61% Impervious, Inflow = 13.97 cfs @ 11.97 hrs, Volume Outflow = 13.97 cfs @ 11.97 hrs, Volume Primary = 13.97 cfs @ 11.97 hrs, Volume Inflow Depth > 4.66" = 0.696 of = 0.696 af, = 0.696 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 445.13' @ 11.97 hrs Device Routing Invert Outlet Devices #1 Primary 426.67' 12.0" Round Culvert L= 80.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 426.67'/ 424.51' S= 0.0270 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=13.59 cfs @ 11.97 hrs HW=444.16' TW=424.70' (Dynamic Tailwater) L1=Culvert (Barrel Controls 13.59 cfs @ 17.30 fps) Summary for Pond SMP -1: Bioretention Inflow Area = 0.990 ac, 33.03% Impervious, Inflow = 4.51 cfs @ 12.08 hrs, Volume Outflow = 4.47 cfs @ 12.10 hrs, Volume Primary = 0.04 cfs @ 12.10 hrs, Volume Secondary = 4.43 cfs @ 12.10 hrs, Volume Inflow Depth > 3.75" = 0.310 of = 0.292 af, = 0.041 of = 0.251 of for 100 -year event Atten= 1 %, Lag= 1.4 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 450.78' @ 12.10 hrs Surf.Area= 1,918 sf Storage= 1,247 cf Plug -Flow detention time= 31.3 min calculated for 0.291 of (94% of inflow) Center -of -Mass det. time= 10.4 min (786.9 - 776.5 ) Volume Invert Avail.Storage Storage Description #1 450.00' 1,694 cf Custom Stage Data (Irregular)Listed below (Recalc) Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area (feet) (sq -ft) (feet) (cubic -feet) (cubic -feet) (sq -ft) 450.00 15308 154.0 0 0 11308 451.00 25113 177.0 15694 11694 15936 Device Routing Invert Outlet Devices #1 Secondary 450.50' 12.0' long x 10.0' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef. (English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 #2 Primary 450.00' 1.000 in/hr Exfiltration over Surface area Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 0 2018 HydroCAD Software Solutions LLC Page 37 Primary OutFlow Max=2.81 cfs @ 12.09 hrs HW=425.44' TW=0.00' (Dynamic Tailwater) Ll =Culvert (Barrel Controls 2.81 cfs @ 8.04 fps) � 2=Orifice/Grate (Passes < 2.70 cfs potential flow) 3=Orifice/Grate (Passes < 23.14 cfs potential flow) Secondary OutFlow Max=69.27 cfs @ 12.09 hrs HW=425.44' TW=0.00' (Dynamic Tailwater) =Broad -Crested Rectangular Weir (Weir Controls 69.27 cfs @ 3.20 fps) Summary for Pond YD2: YD2 to YD6 Inflow Area = 0.938 ac, 36.80% Impervious, Inflow = 5.77 cfs @ 11.99 hrs, Volume Outflow = 5.77 cfs @ 11.99 hrs, Volume Primary = 5.77 cfs @ 11.99 hrs, Volume Inflow Depth > 3.94" = 0.308 of = 0.308 af, = 0.308 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 723.24' @ 12.15 hrs Device Routing Invert Outlet Devices #1 Primary 455.30' 12.0" Round Culvert L= 176.0' Ke= 0.500 Inlet/ Outlet Invert= 455.30'/452.21' S=0.0176'/' Cc= 0.900 n= 0.013, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.99 hrs HW=504.45' TW=535.02' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Summary for Pond YD6: YD6 to CB5 Inflow Area = 1.081 ac, 32.55% Impervious, Inflow = 6.61 cfs @ 11.98 hrs, Volume Outflow = 6.61 cfs @ 11.98 hrs, Volume Primary = 6.61 cfs @ 11.98 hrs, Volume Inflow Depth > 3.84" = 0.346 of = 0.346 af, = 0.346 of for 100 -year event Atten= 0%, Lag= 0.0 min Routing by Dyn-Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 722.42' @ 12.10 hrs Device Routing Invert Outlet Devices #1 Primary 452.11' 12.0" Round Culvert L= 40.0' CPP, square edge headwall, Ke= 0.500 Inlet/ Outlet Invert= 452.11'/450.50' S=0.0403'/' Cc= 0.900 n=0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf Primary OutFlow Max=0.00 cfs @ 11.98 hrs HW=533.30' TW=640.61' (Dynamic Tailwater) L1=Culvert (Controls 0.00 cfs) Post-Dev Skidmore Swing Type 11 24 -hr 100 -year Rainfall=6.20" Prepared by The LA Group Printed 4/12/2019 HydroCADO 10.00-21 s/n 00439 © 2018 HydroCAD Software Solutions LLC Page 38 Summary for Link AP -1: AP -1 Inflow Area = 25.050 ac, 38.36% Impervious, Inflow Depth > 3.46" for 100 -year event Inflow = 94.26 cfs @ 12.09 hrs, Volume= 7.220 of Primary = 94.26 cfs @ 12.09 hrs, Volume= 7.220 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Attachment D Storm Data Stormwater Practice Sizing Job Name and # Skidmore Swing Building Water Quality Volume Calculation 4/12/2019 WQv = [(P)(Rv)(A)l/12 Where: Rv = 0.05 + 0.009(I) I = impervious cover in percent P = 90% rainfall (see Figure 4.1 in NYS Stormwater Management Design Manual) A = Area in acres Required WQv New Impervious % Impervious 100.00% Rv 0.95 90% Rainfall 1.15 Area in Square Feet 28,358 WQv Required = 2582 ft3 0.06 ac -ft Calculated WQv SMP -1 Bioretention (Subcatchment SF4) % Impervious 21.56% Rv 0.24 90% Rainfall 1.15 Area in Square Feet 36,765 WQv Calculated = 860 ft3 0.02 ac -ft SMP -2 Pond Retrofit % Impervious 66.31% Rv 0.65 90% Rainfall 1.15 Area in Square Feet 281445 WQv Calculated = 1763 ft3 0.04 ac -ft Total = 2623 ft 3 I 0.061ac-ft SMP -2 Pond Retrofit - Additional Calculations Permanent Pool Elevation = 421.5 Existing Permanent Pool Volume = 20055 ft3 0.460 ac -ft Proposed Permanent Pool Volume = 29447 ft3 0.676 ac -ft Additional WQv Provided = 9392 ft3 0.216 ac -ft Calculation Summary: The additional WQv provided below the permanent pool elevation (0.216 ac -ft) is greater than the WQv treated 0.04 ac -ft). WQv treatment is therefore being met at the pond. Job Name and # Skidmore Swing Building Minimum Runoff Reduction Volume 4/12/2019 RRv = [(P)(Rv*)(Ai)]/12 Where: Ai = (S)(Aic) Rv = 0.05 + 0.009(I) where I is 100% impervious Ai =impervious cover targeted for runoff reduction Aic =Total area of new impervious cover P = 90% rainfall (see Figure 4.1 in NYS Stormwater Management Design Manual) S =Hydrologic Soil Group (HSG) Specific Reduction Factor (S) A=0.551 B=0.401 C=0.301 D=0.20 S (HSG C/D) Aic Rv (Minimum 0.2) 90% Rainfall Ai 0.26 0.65 acres 0.95 1.15 0.171 RRv = 0.02 acre feet = 677 ft' Skidmore Flex Building 2018135 BIORETENTION WORKSHEET (See Section 6.4.4 of the NYSDEC Stormwater Management Design Manual 2015) Bioretention Area 1 1. Underlying soil permeability = 0.50 in/hr (if no underdrains proposed, must infiltrate within 48 hours, HSG A and B Soils) 2. Calculate WQv: DA (maximum 5 acres) = 36,765 ft2 Percent Impervious Area, 1 = 22% % Rv = .05 +.009 (1) = 0.24 P (90% Rainfall) = 1.15 in. WQv = P Rv A/12 = 860 ft3 75% of WQv 645 ft" 3. Bioretention Details: Material Planting Soil Mix Filter bed depth (df) (2.5 - 4.0 ft) = 2.50 ft Coefficient of permeability of filter media (k) = 1.00 ft/day Avg. height of water above filter media (hf) (max. 0.5 ft; = 0.50 ft Design filter bed drain time (tf) = 2 days 4. Calculate required bioretention surface area (AF): S rfA- WQv x df U ace area ( f) - k (hf + df) (tf) Required Surface Area (Af) = 358 ft 5. Bioretention surface area provided = 1308 ft2 (design) 6. Water Quality Volume provided = 860 ft3 (design) 7. Is Bioretention Basin Lined or in HSG C/D Soils 8. Runoff Reduction Volume provided BR -1 Yes = 860 ft3 (design) Attachment D Job Name Skidmore Swing Building Channel Protection Volume Calculation Pre Development Step 1: Determine Qu P = 2.15 in. (1 -yr. storm) Area = 25.1 acres CN = 82 Ia = 0.439 Ia/P = 0.20 Tc = 0.10 Hrs. Using Figure 4 -II, TR -55 and Tc, determine Qu (csm/in) Qu = 975 csm/in Step 2: Determine Qo/Qi Using Figure B-1, DEC Manual Appendix Bfor T = 24 hrs. and Qu, determine Qo/Qi QO/Qi = 0.02 Step 3: Determine Vs/Vr Vs/Vr = 0.682 - 1.43(Qo/Qi) + 1.64 (QO/Qi)A2 - 0.804 (QO/Qi)A3 Vs/Vr = 0.654 Step 4: Determine Qd Using Figure 2.1, TR -55 or SCS TR -16 and P, determine Qd (in of runoff Qd = 0.79 in Sten 5: Determine Cpv Area = 25.05 acres Cpv = Vs = (Vs/Vr) * Qd * A/12 Cpv = 1.079 ac -ft Cpv = 46984 ft 3 Cpv Req: 46984 ft 3 Job Name Skidmore Swing Building Channel Protection Volume Calculation Post Development Sten 1: Determine Ou P = 2.15 in. (1 -yr. storm) Area = 25.1 acres CN = 83 Ia = 0.410 Ia/P = 0.19 Tc = 0.10 Hrs. Using Figure 4 -II, TR -55 and Tc, determine Qu (csm/in) Qu = 975 csm/in Step 2: Determine Qo/Qi Using Figure B-1, DEC Manual Appendix Bfor T = 24 hrs. and Qu, determine Qo/Qi QO/Qi = 0.02 Sten 3: Determine Vs/Vr Vs/Vr = 0.682 - 1.43(Qo/Qi) + 1.64 (QO/Qi)A2 - 0.804 (QO/Qi)A3 Vs/Vr = 0.654 Step 4: Determine Qd Using Figure 2. 1, TR -55 or SCS TR -16 and P, determine Qd (in of runoff Qd = 0.8 in Step 5: Determine Cpv Area = 25.05 acres Cpv = Vs = (Vs/Vr) * Qd * A/12 Cpv = 1.092 ac -ft Cpv Post = 47579 ft 3 Cpv Pre= 46984 ft3 Cpv Req: 595 ft3 Cpv Provided= 860 ft3 Vegetated Swale Worksheet Enter Site Data For Drainage Area to be Treated by Practice Catchment Number Total Area (Acres) Impervious Percent Rv WQv Precipitation Description Area Impervious (Acres) % (ft3) (in) 1 0.84 0.22 26% 0.28 986 1.15 Vegetated Swale Enter Soil Infiltration Rate Soil Infiltration Rate 1.00 1 in/hour Okay Calculate Peak WQv Modified CN 87 Note: Value is modified curve number using Appendix B.2 - Water Quality Peak Flow Calculation of the New York State Stormwater Management Design Manual la 0.289 la/P 0.251 Tc (hours) 0.24 Note: Tc is a direct entry using the flow path for the catchment draining to the practice qu 750 Note: qu value is taken from TR -55 (either Exhibit 4-11 (Type 11 Rainfall Distribution) or Exhibit 4-111 (Type 111 Rainfall Distribution) depending on the location in the State Qp 0.32 cfs Q10 1.8 cfs From TR -55 Enter Swale Dimensions Bottom Width 5 ft Minimum of 2 ft but no greater than 6 ft Side Slopes 3 :1 Okay Channel Height 1.5 ft Flow Depth 0.11 ft Okay Longitudinal Slope 1.8% Between .5% and 4% (1.5-2.5% Preferred) Swale Length 171.00 ft Mannings Coef. 0.15 Use variable n values corresponding to flow depths (from .15 down to .03) (APPENDIX L) Calculated Swale Dimensions Top Width 5.66 Q 0.2 Area 0.59 ft 2 Velocity 0.29 fps Wetted Perimeter 1 5.70 Ift I Detention Time 9.87 minutes Determine Required Length Of Channel Required Length 171.00 ft Length Provided 171.00 ft Q10 Velocity 1.80 fps Okay Q10 flow depth 1.32 inches Q10 freeboard 10.68 1 inches Okay Determine Runoff Reduction Soil Group C Percent Reduction 0.10 Is the Vegetated Swale contributing flow to another practice? Yes Select Practice Bioretention Runoff Reduction 99 ft3 Portion of WQv not reduced that must be directed to a standard SMP 888 ft3 Appendix D SWPPP Inspection Form Skidmore College Swing Building WEEKLY SWPPP INSPECTION REPORT Inspector Name: Date: Signature (required): Time: Weather: I Inspection #: Soil Conditions (dry, saturated, etc): j Note: Digital photos, with date stamp required for all practices requiring corrective action, before and after, to be attached to the inspection report. YES NO N/A 1. ❑ ❑ ❑ 2. Routine Inspection. Date of last inspection: Inspection following rain event. Date/time of storm ending: Rainfall amount: Recorded by: 3. ❑ ❑ ❑ Is this a final site inspection? 4. ❑ ❑ ❑ Has site undergone final stabilization? ❑ ❑ ❑ If so, have all temporary erosion and sediment controls been removed? Site Disturbance (Indicate Locations on Plan) YES NO N/A 1. ❑ ❑ ❑ Areas previously disturbed, but have not undergone active site work in the last 14 days? 2. ❑ ❑ ❑ Areas disturbed within last 14 days? 3. ❑ ❑ ❑ Areas expected to be disturbed in next 14 days? 4. ❑ ❑ ❑ Do areas of steep slopes or complex stabilization issues exist? If "YES" explain: 5. ❑ ❑ ❑ Are there currently more than 5 acres of disturbed soil at the site? If so make sure there is an approval letter from NYS DEC. Additional Comments: Inspection of Erosion and Sediment Control Devices Type of Control Device Accumulation (if any) in % Repairs/Maintenance Needed 1. 2. 3. 4. 5. 6. Stabilization/Runoff YES NO N/A 1. ❑ ❑ ❑ Are all existing disturbed areas contained by control devices? Type of devices: 2. ❑ ❑ ❑ Are there areas that require stabilization within the next 14 days? Specify Area: 3. ❑ ❑ ❑ Have stabilization measures been initiated in inactive areas? 4. ❑ ❑ ❑ Is there current snow cover or frozen ground conditions? 5. ❑ ❑ ❑ Rills or gullies? 6. ❑ ❑ ❑ Slumping/deposition? 7. ❑ ❑ ❑ Loss of vegetation? 8. ❑ ❑ ❑ Lack of germination? 9. ❑ ❑ ❑ Loss of mulching? Receiving Structures/Water Bodies (Indicate locations where runoff leaves the project site on the site plan) YES NO N/A 1. ❑ ❑ ❑ Surface water swale or natural surface waterbody? If natural waterbody: Is waterbody located ❑ onsite, or ❑ adjacent to property boundary? Description of condition: 2. ❑ ❑ ❑ Municipal or community system? Inspect locations where runoff from project site enters the receiving waters and indicate if there is evidence of: a. ❑ ❑ ❑ Rills or gullies? b. ❑ ❑ ❑ Slumping/deposition? c. ❑ ❑ ❑ Loss of vegetation? d. ❑ ❑ ❑ Undermining of structures? e. ❑ ❑ ❑ Was there a discharge into the receiving water on the day of inspection? f. ❑ ❑ ❑ Is there evidence of turbidity, sedimentation, or oil in the receiving waters? Additional Comments: Inspection of Post -Construction Stormwater Management Control Devices Type of Control Device Phase of Construction Repairs/Maintenance Needed 1. 2. 3. 4. General Site Condition YES NO N/A 1. ❑ ❑ ❑ Have action items from previous reports been addressed? 2. ❑ ❑ ❑ Does routine maintenance of protection components occur on a regular basis? 3. ❑ ❑ ❑ Does cleaning and/or sweeping affected roadways occur, at minimum, daily? 4. ❑ ❑ ❑ Is debris and litter removed on a monthly basis, or as necessary? 5. ❑ ❑ ❑ Is the site maintained in an orderly manner? Describe the condition of all natural waterbodies within or adjacent to the Project that receive runoff from the site: Contractors progress over last 7 days: Anticipated work to be begun in the next 7 days: Additional Comments: Visual Observations YES NO N/A 1. ❑ ❑ ❑ All erosion and sediment control measures have been installed/constructed? 2. ❑ ❑ ❑ All erosion and sediment control measures are being maintained properly? SUMMARY OF ACTION ITEMS TO REPAIR/REPLACE/MAINTAIN/CORRECT DEFICIENCIES Action Reported To (no signature required): Company: Appendix E Other SWPPP Forms Construction Sequence SWPPP Plan Changes Spill Response Form Stormwater Management Practice Maintenance Log The operator shall prepare a summary of construction status using the Construction Sequence Form below once every month. Significant deviations to the sequence and reasons for those deviations (i.e. weather, subcontractor availability, etc.), shall be noted by the contractor. The schedule shall be used to record the dates for initiation of construction, implementation of erosion control measures, stabilization, etc. A copy of this table will be maintained at the construction site and updated in addition to the individual Inspection Reports completed for each inspection. Construction Sequence Form Construction Activities Date (Identify name of planned practices) Complete 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. STORM WATER POLLUTION PREVENTION PLAN PLAN CHANGES, AUTHORIZATION, AND CHANGE CERTIFICATION CHANGES REQUIRED TO THE POLLUTION PREVENTION PLAN: REASONS FOR CHANGES: REQUESTED BY: DATE: AUTHORIZED BY: DATE: CERTIFICATION OF CHANGES: certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that false statements made herein are punishable as a Class A misdemeanor pursuant to Section 210.45 of the penal code. SIGNATURE: DATE: SPILL RESPONSE REPORT Within 1 hour of a spill discovery less than 2 gallons in volume the following must be notified: Dan Rodecker (518) 580-5860 Within 1 hour of a spill discovery greater than 2 gallons the following must be notified: Dan Rodecker NYSDEC Spill Response Hotline 1-800-457-7362 Spill Response Contractor Material Spilled: Approximate Volume: Location: Distance to nearest down gradient drainage: Distance to nearest down gradient open water: Temporary control measures in place: L The LA GROUP Site Name: Location: Owner Name: Address: Site Status: Date: Time: Bioretention Site Conditions: Stormwater Pond Type: F-1 Wet Pond ❑Wet ED Pond ❑ Mircropool Pond ❑Multiple Pond System F-1 Dry Pond Inspection Items p Maintenance Needed? (Yes/No) Comments/Description Debris Removal Contributing area free of debris? Inlet/Inflow pipes free of debris? Contributing area free of erosion? Infiltration Area Standing water longer than 24 hours after a storm event? Sediment observed at inlet or outlet of infiltration area? Structural damage? Slumping in or around infiltration area? Vegetation healthy? Animal burrows? Inspector Comments: Overall Condition of Facility: ❑ Acceptable ❑ Unacceptable If any of the above inspection items are checked "Yes" for "Maintenance Needed," list maintenance actions and their completion dates below: Maintenance Action Needed Due Date Inspected by: (signature) Inspected by: (printed) L The LA GROUP Stormwater Pond Site Name: Location: Owner Name: Address: Site Status: Date: Time: Site Conditions: Inspection Items p Maintenance Needed?(Yes/No) Comments/Description Embankment and Emergency Spillway (Annual, After Major Storms) Adequate vegetation and cover? Embankment erosion? Animal burrows? Unauthorized plantings? Cracking, bulging, sliding of dam? - On the upstream, downstream, at or beyond toe (upstream or downstream), emergency spillway? Pond, toe, & chimney drains clear and functioning? Are there seaps or leaks on downstream face? Slope protection or rip rap failure? Emergency spillway clear of obstructions and debris? Riser and Principal Spillway (Annual) Low flow obstructed? Trash removal from any of the orifices and weir? Excessive sediment accumulation insider riser? Concrete masonry condition riser and barrels? Metal pipe condition? Control valve condition? Pond drain valve condition? Are outfall channels functioning? Permanent Pool (Wet Pools) (Monthly) Undesirable vegetation growth? Floating/floatables removal? Visible pollution? Shoreline issues? Dry Pond Areas Riprap failures? Slope erosion? Storm drain pipes? L The LA GROUP Endwalls/headwalls? Other Encroachment on pond? Complaints from neighbors/residents? Aesthetic issues? Conditions of maintenance access routes? Signs of hydrocarbon build-up? Any public hazards? Inspector Comments: Overall Condition of Facility: ❑ Acceptable ❑ Unacceptable If any of the above inspection items are checked "Yes" for "Maintenance Needed," list maintenance actions and their completion dates below: Maintenance Action Needed Due Date Inspected by: (signature) Inspected by: (printed) Appendix F SPDES General Permit GP -0-15-002 I r EW YORK [department cif 011 R��,�;��Y Environmental -} £ortserVati0n NEW YORK STATE DEPARTMENT OF ENVIRONMENTAL CONSERVATION SPDES GENERAL PERMIT FOR STORMWATER DISCHARGES From CONSTRUCTION ACTIVITY Permit No. P-0-15-002 issued Pursuant to Article 17. . Titles 7, 8 and Article 70 of the Environmental Conservation Law Effective Dale: January 29. 2015 Expiration Date: January 28, 2020 Modificatian Date: July 14, 015 - Correction of typographical error in definition of "New Devrelopnaenr, Appendix A John J_ Fergus-Gn C hie( Permit Administrator Ut {}feZ inat�a--Date Addressu- NYS DEC Division of Environmental Permits 625 Broadway, 4th Floor Albany, N.Y. 12233-1750 NEW YORK STATE DEPARTMENT OF ENVIRONMENTAL CONSERVATION SPDES GENERAL PERMIT FOR STORMWATER DISCHARGES FROM CONSTRUCTION ACTIVITIES Part I. PERMIT COVERAGE AND LIMITATIONS..............................................................1 A. Permit Application.................................................................................................1 B. Effluent Limitations Applicable to Discharges from Construction Activities ...........1 C. Post -construction Stormwater Management Practice Requirements ....................4 D. Maintaining Water Quality.....................................................................................8 E. Eligibility Under This General Permit.....................................................................9 F. Activities Which Are Ineligible for Coverage Under This General Permit ..............9 Part II. OBTAINING PERMIT COVERAGE.....................................................................12 A. Notice of Intent (NOI) Submittal..........................................................................12 B. Permit Authorization............................................................................................13 C. General Requirements For Owners or Operators With Permit Coverage ...........15 D. Permit Coverage for Discharges Authorized Under GP -0-10-001 .......................17 E. Change of Owner or Operator.............................................................................17 Part III. STORMWATER POLLUTION PREVENTION PLAN(SWPPP)...........................18 A. General SWPPP Requirements..........................................................................18 B. Required SWPPP Contents................................................................................20 C. Required SWPPP Components by Project Type.................................................23 Part IV. INSPECTION AND MAINTENANCE REQUIREMENTS.....................................24 A. General Construction Site Inspection and Maintenance Requirements ..............24 B. Contractor Maintenance Inspection Requirements.............................................24 C. Qualified Inspector Inspection Requirements......................................................24 Part V. TERMINATION OF PERMIT COVERAGE...........................................................28 A. Termination of Permit Coverage.........................................................................28 Part VI. REPORTING AND RETENTION OF RECORDS................................................30 A. Record Retention................................................................................................30 B. Addresses...........................................................................................................30 Part VII. STANDARD PERMIT CONDITIONS.................................................................31 A. Duty to Comply....................................................................................................31 B. Continuation of the Expired General Permit........................................................31 C. Enforcement........................................................................................................31 D. Need to Halt or Reduce Activity Not a Defense...................................................31 E. Duty to Mitigate...................................................................................................32 F. Duty to Provide Information.................................................................................32 G. Other Information................................................................................................32 H. Signatory Requirements......................................................................................32 I. Property Rights.......................................................................................................34 J. Severability.............................................................................................................34 K. Requirement to Obtain Coverage Under an Alternative Permit ...........................34 L. Proper Operation and Maintenance....................................................................35 M. Inspection and Entry...........................................................................................35 N. Permit Actions.....................................................................................................36 O. Definitions...........................................................................................................36 P. Re -Opener Clause..............................................................................................36 PREFACE Pursuant to Section 402 of the Clean Water Act ("CWA"), stormwater discharges from certain construction activities are unlawful unless they are authorized by a National Pollutant Discharge Elimination System ("NPDES') permit or by a state permit program. New York's State Pollutant Discharge Elimination System ("SPDES') is a NPDES- approved program with permits issued in accordance with the Environmental Conservation Law ("ECL'). This general permit ("permit") is issued pursuant to Article 17, Titles 7, 8 and Article 70 of the ECL. An owner or operator may obtain coverage under this permit by submitting a Notice of Intent ("NOI") to the Department. Copies of this permit and the NOI for New York are available by calling (518) 402-8109 or at any New York State Department of Environmental Conservation ("the Department") regional office (see Appendix G).They are also available on the Department's website at- http://www.dec.nv.qov/ An owner or operator of a construction activity that is eligible for coverage under this permit must obtain coverage prior to the commencement of construction activity. Activities that fit the definition of "construction activity', as defined under 40 CFR 122.26(b)(14)(x), (15)(i), and (15)(ii), constitute construction of a point source and therefore, pursuant to Article 17-0505 of the ECL, the owner or operator must have coverage under a SPDES permit prior to commencing construction activity. They cannot wait until there is an actual discharge from the construction site to obtain permit coverage. *Note: The italicized words/phrases within this permit are defined in Appendix A. Q. Penalties for Falsification of Forms and Reports.................................................36 R. Other Permits......................................................................................................36 APPENDIXA....................................................................................................................37 APPENDIXB....................................................................................................................44 APPENDIXC...................................................................................................................46 APPENDIXD...................................................................................................................52 APPENDIXE....................................................................................................................53 APPENDIXF....................................................................................................................55 (Part 1) Part I. PERMIT COVERAGE AND LIMITATIONS A. Permit Application This permit authorizes stormwater discharges to surface waters of the State from the following construction activities identified within 40 CFR Parts 122.26(b)(14)(x), 122.26(b)(1 5)(i) and 122.26(b)(15)(ii), provided all of the eligibility provisions of this permit are met: 'i Construction activities involving soil disturbances of one (1) or more acres; including disturbances of less than one acre that are part of a larger common plan of development or sale that will ultimately disturb one or more acres of land; excluding routine maintenance activity that is performed to maintain the original line and grade, hydraulic capacity or original purpose of a facility; Construction activities involving soil disturbances of less than one (1) acre where the Department has determined that a SPDES permit is required for stormwater discharges based on the potential for contribution to a violation of a water quality standard or for significant contribution of pollutants to surface waters of the State. 3. Construction activities located in the watershed(s) identified in Appendix D that involve soil disturbances between five thousand (5,000) square feet and one (1) acre of land. B. Effluent Limitations Applicable to Discharges from Construction Activities Discharges authorized by this permit must achieve, at a minimum, the effluent limitations in Part 1.B.1. (a) — (f) of this permit. These limitations represent the degree of effluent reduction attainable by the application of best practicable technology currently available._ 1. Erosion and Sediment Control Requirements - The owner or operator must select, design, install, implement and maintain control measures to minimize the discharge of pollutants and prevent a violation of the water quality standards. The selection, design, installation, implementation, and maintenance of these control measures must meet the non -numeric effluent limitations in Part I.B.1.(a) — (f) of this permit and be in accordance with the New York State Standards and Specifications for Erosion and Sediment Control, dated August 2005, using sound engineering judgment. Where control measures are not designed in conformance with the design criteria included in the technical standard, the owner or operator must include in the Stormwater Pollution Prevention Plan ("SWPPP") the reason(s) for the deviation or alternative design and provide information 1 (Part 1.B.1) (Part I.B.1.c) (Part I.B.1.f) from dewatering of trenches and excavations, must be managed by appropriate control measures. d. Pollution Prevention Measures. Design, install, implement, and maintain effective pollution prevention measures to minimize the discharge of pollutants and prevent a violation of the water quality standards. At a minimum, such measures must be designed, installed, implemented and maintained to: (i) Minimize the discharge of pollutants from equipment and vehicle washing, wheel wash water, and other wash waters. This applies to washing operations that use clean water only. Soaps, detergents and solvents cannot be used; (ii) Minimize the exposure of building materials, building products, construction wastes, trash, landscape materials, fertilizers, pesticides, herbicides, detergents, sanitary waste and other materials present on the site to precipitation and to stormwater. Minimization of exposure is not required in cases where the exposure to precipitation and to stormwater will not result in a discharge of pollutants, or where exposure of a specific material or product poses little risk of stormwater contamination (such as final products and materials intended for outdoor use) ; and (iii) Prevent the discharge of pollutants from spills and leaks and implement chemical spill and leak prevention and response procedures. e. Prohibited Discharges. The following discharges are prohibited: (i) Wastewater from washout of concrete; (ii) Wastewater from washout and cleanout of stucco, paint, form release oils, curing compounds and other construction materials; (iii) Fuels, oils, or other pollutants used in vehicle and equipment operation and maintenance; (iv) Soaps or solvents used in vehicle and equipment washing; and (v) Toxic or hazardous substances from a spill or other release. f. Surface Outlets. When discharging from basins and impoundments, the outlets shall be designed, constructed and maintained in such a manner that sediment does not leave the basin or impoundment and that erosion 3 which demonstrates that the deviation or alternative design is equivalent to the technical standard. a. Erosion and Sediment Controls. Design, install and maintain effective erosion and sediment controls to minimize the discharge of pollutants and prevent a violation of the water quality standards. At a minimum, such controls must be designed, installed and maintained to: (i) Minimize soil erosion through application of runoff control and soil stabilization control measure to minimize pollutant discharges; (ii) Control stormwater discharges to minimize channel and streambank erosion and scour in the immediate vicinity of the discharge points; (iii) Minimize the amount of soil exposed during construction activity; (iv) Minimize the disturbance of steep slopes; (v) Minimize sediment discharges from the site; (vi) Provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas and maximize stormwater infiltration to reduce pollutant discharges, unless infeasible; (vii) Minimize soil compaction. Minimizing soil compaction is not required where the intended function of a specific area of the site dictates that it be compacted; and (viii) Unless infeasible, preserve a sufficient amount of topsoil to complete soil restoration and establish a uniform, dense vegetative cover. b. Soil Stabilization. In areas where soil disturbance activity has temporarily or permanently ceased, the application of soil stabilization measures must be initiated by the end of the next business day and completed within fourteen (14) days from the date the current soil disturbance activity ceased. For construction sites that directly discharge to one of the 303(d) segments listed in Appendix E or is located in one of the watersheds listed in Appendix C, the application of soil stabilization measures must be initiated by the end of the next business day and completed within seven (7) days from the date the current soil disturbance activity ceased. See Appendix A for definition of Temporarily Ceased. c. Dewatering. Discharges from dewatering activities, including discharges 2 at or below the outlet does not occur. C. Post -construction Stormwater Management Practice Requirements 1. The owner or operator of a construction activity that requires post - construction stormwater management practices pursuant to Part III.C. of this permit must select, design, install, and maintain the practices to meet the performance criteria in the New York State Stormwater Management Design Manual ("Design Manual"), dated January 2015, using sound engineering judgment. Where post -construction stormwater management practices ("SMPs") are not designed in conformance with the performance criteria in the Design Manual, the owner or operator must include in the SWPPP the reason(s) for the deviation or alternative design and provide information which demonstrates that the deviation or alternative design is equivalent to the technical standard. The owner or operator of a construction activity that requires post - construction stormwater management practices pursuant to Part III.C. of this permit must design the practices to meet the applicable sizing criteria in Part I.C.2.a., b., c. or d. of this permit. a. Sizing Criteria for New Development (i) Runoff Reduction Volume ("RRv"): Reduce the total Water Quality Volume ("WQv") by application of RR techniques and standard SMPs with RRv capacity. The total WQv shall be calculated in accordance with the criteria in Section 4.2 of the Design Manual. (ii) Minimum RRv and Treatment of Remaining Total WQv: Construction activities that cannot meet the criteria in Part I.C.2.a.(i) of this permit due to site limitations shall direct runoff from all newly constructed impervious areas to a RR technique or standard SMP with RRv capacity unless infeasible. The specific site limitations that prevent the reduction of 100% of the WQv shall be documented in the SWPPP. For each impervious area that is not directed to a RR technique or standard SMP with RRv capacity, the SWPPP must include documentation which demonstrates that all options were considered and for each option explains why it is considered infeasible. In no case shall the runoff reduction achieved from the newly constructed impervious areas be less than the Minimum RRv as calculated using the criteria in Section 4.3 of the Design Manual. The remaining portion of the total WQv 4 (Part I.C.2.a.ii) (Part I.C.2.c.i) that cannot be reduced shall be treated by application of standard SMPs. (iii) Channel Protection Volume ("Cpv"): Provide 24 hour extended detention of the post -developed 1 -year, 24-hour storm event; remaining after runoff reduction. The Cpv requirement does not apply when: (1) Reduction of the entire Cpv is achieved by application of runoff reduction techniques or infiltration systems, or (2) The site discharges directly to tidal waters, or fifth order or larger streams. (iv) Overbank Flood Control Criteria ("Qp"): Requires storage to attenuate the post -development 10 -year, 24-hour peak discharge rate (Qp) to predevelopment rates. The Qp requirement does not apply when: (1) the site discharges directly to tidal waters or fifth order or larger streams, or (2) A downstream analysis reveals that overbank control is not required. (v) Extreme Flood Control Criteria ("Qf'): Requires storage to attenuate the post -development 100 -year, 24-hour peak discharge rate (Qf) to predevelopment rates. The Qf requirement does not apply when: (1) the site discharges directly to tidal waters or fifth order or larger streams, or (2) A downstream analysis reveals that overbank control is not required. b. Sizing Criteria for New Development in Enhanced Phosphorus Removal Watershed (i) Runoff Reduction Volume (RRv): Reduce the total Water Quality Volume (WQv) by application of RR techniques and standard SMPs with RRv capacity. The total WQv is the runoff volume from the 1 -year, 24 hour design storm over the post -developed watershed and shall be calculated in accordance with the criteria in Section 10.3 of the Design Manual. (ii) Minimum RRv and Treatment of Remaining Total WQv: Construction activities that cannot meet the criteria in Part I.C.2.b.(i) of this permit due to site limitations shall direct runoff from all newly constructed impervious areas to a RR technique or (i) Water Quality Volume (WQv): The WQv treatment objective for redevelopment activity shall be addressed by one of the following options. Redevelopment activities located in an Enhanced Phosphorus Removal Watershed (see Part III.6.3. and Appendix C of this permit) shall calculate the WQv in accordance with Section 10.3 of the Design Manual. All other redevelopment activities shall calculate the WQv in accordance with Section 4.2 of the Design Manual. (1) Reduce the existing impervious cover by a minimum of 25% of the total disturbed, impervious area. The Soil Restoration criteria in Section 5.1.6 of the Design Manual must be applied to all newly created pervious areas, or (2) Capture and treat a minimum of 25% of the WQv from the disturbed, impervious area by the application of standard SMPs; or reduce 25% of the WQv from the disturbed, impervious area by the application of RR techniques or standard SMPs with RRv capacity., or (3) Capture and treat a minimum of 75% of the WQv from the disturbed, impervious area as well as any additional runoff from tributary areas by application of the alternative practices discussed in Sections 9.3 and 9.4 of the Design Manual., or (4) Application of a combination of 1, 2 and 3 above that provide a weighted average of at least two of the above methods. Application of this method shall be in accordance with the criteria in Section 9.2.1(8) (IV) of the Design Manual. If there is an existing post -construction stormwater management practice located on the site that captures and treats runoff from the impervious area that is being disturbed, the WQv treatment option selected must, at a minimum, provide treatment equal to the treatment that was being provided by the existing practice(s) if that treatment is greater than the treatment required by options 1 — 4 above. (ii) Channel Protection Volume (Cpv): Not required if there are no changes to hydrology that increase the discharge rate from the project site. (iii) Overbank Flood Control Criteria (Qp): Not required if there are no changes to hydrology that increase the discharge rate from the project site. (Part I.C.2.b.ii) standard SMP with RRv capacity unless infeasible. The specific site limitations that prevent the reduction of 100% of the WQv shall be documented in the SWPPP. For each impervious area that is not directed to a RR technique or standard SMP with RRv capacity, the SWPPP must include documentation which demonstrates that all options were considered and for each option explains why it is considered infeasible. In no case shall the runoff reduction achieved from the newly constructed impervious areas be less than the Minimum RRv as calculated using the criteria in Section 10.3 of the Design Manual. The remaining portion of the total WQv that cannot be reduced shall be treated by application of standard SMPs. (iii) Channel Protection Volume (Cpv): Provide 24 hour extended detention of the post -developed 1 -year, 24-hour storm event; remaining after runoff reduction. The Cpv requirement does not apply when: (1) Reduction of the entire Cpv is achieved by application of runoff reduction techniques or infiltration systems, or (2) The site discharges directly to tidal waters, or fifth order or larger streams. (iv) Overbank Flood Control Criteria (Qp): Requires storage to attenuate the post -development 10 -year, 24-hour peak discharge rate (Qp) to predevelopment rates. The Qp requirement does not apply when: (1) the site discharges directly to tidal waters or fifth order or larger streams, or (2) A downstream analysis reveals that overbank control is not required. (v) Extreme Flood Control Criteria (Qf): Requires storage to attenuate the post -development 100 -year, 24-hour peak discharge rate (Qf) to predevelopment rates. The Qf requirement does not apply when: (1) the site discharges directly to tidal waters or fifth order or larger streams, or (2) A downstream analysis reveals that overbank control is not required. c. Sizing Criteria for Redevelopment Activity 6 (Part I.C.2.c.iv) (iv) Extreme Flood Control Criteria (Qf): Not required if there are no changes to hydrology that increase the discharge rate from the project site. d. Sizing Criteria for Combination of Redevelopment Activity and New Development Construction projects that include both New Development and Redevelopment Activity shall provide post -construction stormwater management controls that meet the sizing criteria calculated as an aggregate of the Sizing Criteria in Part I.C.2.a. or b. of this permit for the New Development portion of the project and Part I.C.2.c of this permit for Redevelopment Activity portion of the project. D. Maintaining Water Quality The Department expects that compliance with the conditions of this permit will control discharges necessary to meet applicable water quality standards. It shall be a violation of the ECL for any discharge to either cause or contribute to a violation of water quality standards as contained in Parts 700 through 705 of Title 6 of the Official Compilation of Codes, Rules and Regulations of the State of New York, such as: There shall be no increase in turbidity that will cause a substantial visible contrast to natural conditions; 2 There shall be no increase in suspended, colloidal or settleable solids that will cause deposition or impair the waters for their best usages; and 3. There shall be no residue from oil and floating substances, nor visible oil film, nor globules of grease. If there is evidence indicating that the stormwater discharges authorized by this permit are causing, have the reasonable potential to cause, or are contributing to a violation of the water quality standards; the owner or operator must take appropriate corrective action in accordance with Part IV.C.5. of this general permit and document in accordance with Part IV.C.4. of this general permit. To address the water quality standard violation the owner or operator may need to provide additional information, include and implement appropriate controls in the SWPPP to correct the problem, or obtain an individual SPDES permit. If there is evidence indicating that despite compliance with the terms and conditions of this general permit it is demonstrated that the stormwater discharges authorized by this permit are causing or contributing to a violation of water quality standards, or (Part I.D) if the Department determines that a modification of the permit is necessary to prevent a violation of water quality standards, the authorized discharges will no longer be eligible for coverage under this permit. The Department may require the owner or operator to obtain an individual SPDES permit to continue discharging. E. Eligibility Under This General Permit 1 . This permit may authorize all discharges of stormwater from construction activity to surface waters of the State and groundwaters except for ineligible discharges identified under subparagraph F. of this Part. 2 Except for non-stormwater discharges explicitly listed in the next paragraph, this permit only authorizes stormwater discharges from construction activities. Notwithstanding paragraphs EA and E.2 above, the following non- stormwater discharges may be authorized by this permit: discharges from firefighting activities; fire hydrant flushings; waters to which cleansers or other components have not been added that are used to wash vehicles or control dust in accordance with the SWPPP, routine external building washdown which does not use detergents; pavement washwaters where spills or leaks of toxic or hazardous materials have not occurred (unless all spilled material has been removed) and where detergents are not used; air conditioning condensate; uncontaminated groundwater or spring water; uncontaminated discharges from construction site de -watering operations; and foundation or footing drains where flows are not contaminated with process materials such as solvents. For those entities required to obtain coverage under this permit, and who discharge as noted in this paragraph, and with the exception of flows from firefighting activities, these discharges must be identified in the SWPPP. Under all circumstances, the owner or operator must still comply with water quality standards in Part LD of this permit. 4. The owner or operator must maintain permit eligibility to discharge under this permit. Any discharges that are not compliant with the eligibility conditions of this permit are not authorized by the permit and the owner or operator must either apply for a separate permit to cover those ineligible discharges or take steps necessary to make the discharge eligible for coverage. F. Activities Which Are Ineligible for Coverage Under This General Permit All of the following are not authorized by this permit: (Part I.F.8) 8. Construction activities that have the potential to affect an historic property, unless there is documentation that such impacts have been resolved. The following documentation necessary to demonstrate eligibility with this requirement shall be maintained on site in accordance with Part II.C.2 of this permit and made available to the Department in accordance with Part VII.F of this permit: a. Documentation that the construction activity is not within an archeologically sensitive area indicated on the sensitivity map, and that the construction activity is not located on or immediately adjacent to a property listed or determined to be eligible for listing on the National or State Registers of Historic Places, and that there is no new permanent building on the construction site within the following distances from a building, structure, or object that is more than 50 years old, or if there is such a new permanent building on the construction site within those parameters that NYS Office of Parks, Recreation and Historic Preservation (OPRHP), a Historic Preservation Commission of a Certified Local Government, or a qualified preservation professional has determined that the building, structure, or object more than 50 years old is not historically/archeologically significant. ■ 1-5 acres of disturbance - 20 feet ■ 5-20 acres of disturbance - 50 feet ■ 20+ acres of disturbance - 100 feet, or b. DEC consultation form sent to OPRHP, and copied to the NYS DEC Agency Historic Preservation Officer (APO), and (i) the State Environmental Quality Review (SEAR) Environmental Assessment Form (EAF) with a negative declaration or the Findings Statement, with documentation of OPRHP's agreement with the resolution; or (ii) documentation from OPRHP that the construction activity will result in No Impact; or (iii) documentation from OPRHP providing a determination of No Adverse Impact; or (iv) a Letter of Resolution signed by the owner/operator, OPRHP and the DEC APO which allows for this construction activity to be eligible for coverage under the general permit in terms of the State Historic Preservation Act (SHPA); or c. Documentation of satisfactory compliance with Section 106 of the National Historic Preservation Act for a coterminous project area: (i) No Affect (ii) No Adverse Affect (Part I.F) 1 Discharges after construction activities have been completed and the site has undergone final stabilization; f' Discharges that are mixed with sources of non-stormwater other than those expressly authorized under subsection E.3. of this Part and identified in the SWPPP required by this permit; 3. Discharges that are required to obtain an individual SPDES permit or another SPDES general permit pursuant to Part VII.K. of this permit; 4. Construction activities or discharges from construction activities that may adversely affect an endangered or threatened species unless the owner or operator has obtained a permit issued pursuant to 6 NYCRR Part 182 for the project or the Department has issued a letter of non -jurisdiction for the project. All documentation necessary to demonstrate eligibility shall be maintained on site in accordance with Part II.C.2 of this permit. n. Discharges which either cause or contribute to a violation of water quality standards adopted pursuant to the ECL and its accompanying regulations; 6. Construction activities for residential, commercial and institutional projects: a. Where the discharges from the construction activities are tributary to waters of the state classified as AA or AA -s; and b. Which disturb one or more acres of land with no existing impervious cover, and c. Which are undertaken on land with a Soil Slope Phase that is identified as an E or F, or the map unit name is inclusive of 25% or greater slope, on the United States Department of Agriculture ("USDA") Soil Survey for the County where the disturbance will occur. 7. Construction activities for linear transportation projects and linear utility projects: a. Where the discharges from the construction activities are tributary to waters of the state classified as AA or AA -s; and b. Which disturb two or more acres of land with no existing impervious cover, and c. Which are undertaken on land with a Soil Slope Phase that is identified as an E or F, or the map unit name is inclusive of 25% or greater slope, on the USDA Soil Survey for the County where the disturbance will occur. 10 (Part I.F.8.c.iii) (iii) Executed Memorandum of Agreement, or d. Documentation that: (i) SHPA Section 14.09 has been completed by NYS DEC or another state agency. 9. Discharges from construction activities that are subject to an existing SPDES individual or general permit where a SPDES permit for construction activity has been terminated or denied; or where the owner or operator has failed to renew an expired individual permit. Part II. OBTAINING PERMIT COVERAGE A.Notice of Intent (NOI) Submittal 1 An owner or operator of a construction activity that is not subject to the requirements of a regulated, traditional land use control MS4 must first prepare a SWPPP in accordance with all applicable requirements of this permit and then submit a completed NOI form to the Department in order to be authorized to discharge under this permit. An owner or operator shall use either the electronic (eNO1) or paper version of the NOI that the Department prepared. Both versions of the NOI are located on the Department's website (http://www.dec.ny.gov/ ). The paper version of the NOI shall be signed in accordance with Part VII.H. of this permit and submitted to the following address. NOTICE OF INTENT NYS DEC, Bureau of Water Permits 625 Broadway, 4t" Floor Albany, New York 12233-3505 2 An owner or operator of a construction activity that is subject to the requirements of a regulated, traditional land use control MS4 must first prepare a SWPPP in accordance with all applicable requirements of this permit and then have its SWPPP reviewed and accepted by the regulated, traditional land use control MS4 prior to submitting the NOI to the Department. The owner or operator shall have the "MS4 SWPPP Acceptance" form signed in accordance with Part VII.H., and then submit that form along with a completed NOI to the Department. An owner or operator shall use either the electronic (eNO1) or paper version of the NOI. The paper version of the NOI shall be signed in accordance with Part VII.H. of this permit and submitted to the address in Part II.A.1. 12 (Part II.A.2) The requirement for an owner or operator to have its SWPPP reviewed and accepted by the MS4 prior to submitting the NOI to the Department does not apply to an owner or operator that is obtaining permit coverage in accordance with the requirements in Part II.E. (Change of Owner or Operator) or where the owner or operator of the construction activity is the regulated, traditional land use control MS4. 3. The owner or operator shall have the SWPPP preparer sign the "SWPPP Preparer Certification" statement on the NOI prior to submitting the form to the Department. 4. As of the date the NOI is submitted to the Department, the owner or operator shall make the NOI and SWPPP available for review and copying in accordance with the requirements in Part VII.F. of this permit. B. Permit Authorization (Part 11.6.4) 1 An owner or operator shall not commence construction activity until their authorization to discharge under this permit goes into effect. 2 Authorization to discharge under this permit will be effective when the owner or operator has satisfied all of the following criteria: a. project review pursuant to the State Environmental Quality Review Act ("SEQRA") have been satisfied, when SEQRA is applicable. See the Department's website (http://www.dec.ny.gov/) for more information, b. where required, all necessary Department permits subject to the Uniform Procedures Act ("UPA') (see 6 NYCRR Part 621) have been obtained, unless otherwise notified by the Department pursuant to 6 NYCRR 621.3(a)(4). Owners or operators of construction activities that are required to obtain UPA permits must submit a preliminary SWPPP to the appropriate DEC Permit Administrator at the Regional Office listed in Appendix F at the time all other necessary UPA permit applications are submitted. The preliminary SWPPP must include sufficient information to demonstrate that the construction activity qualifies for authorization under this permit, c. the final SWPPP has been prepared, and d. a complete NOI has been submitted to the Department in accordance with the requirements of this permit. 3. An owner oroperatorthat has satisfied the requirements of Part 11.6.2 above 13 under this permit if the Department determines that the SWPPP does not meet the permit requirements. In accordance with statute, regulation, and the terms and conditions of this permit, the Department may deny coverage under this permit and require submittal of an application for an individual SPDES permit based on a review of the NOI or other information pursuant to Part 11. ;. Coverage under this permit authorizes stormwater discharges from only those areas of disturbance that are identified in the NOI. If an owner or operator wishes to have stormwater discharges from future or additional areas of disturbance authorized, they must submit a new NOI that addresses that phase of the development, unless otherwise notified by the Department. The owner or operator shall not commence construction activity on the future or additional areas until their authorization to discharge under this permit goes into effect in accordance with Part II.B. of this permit. C. General Requirements For Owners or Operators With Permit Coverage .i The owner or operator shall ensure that the provisions of the SWPPP are implemented from the commencement of construction activity until all areas of disturbance have achieved final stabilization and the Notice of Termination ("NOT") has been submitted to the Department in accordance with Part V. of this permit. This includes any changes made to the SWPPP pursuant to Part III.A.4. of this permit. 2 The owner or operator shall maintain a copy of the General Permit (GP -0- 15-002), NOI, N01 Acknowledgment Letter, SWPPP, MS4 SWPPP Acceptance form, inspection reports, and all documentation necessary to demonstrate eligibility with this permit at the construction site until all disturbed areas have achieved final stabilization and the NOT has been submitted to the Department. The documents must be maintained in a secure location, such as a job trailer, on-site construction office, or mailbox with lock. The secure location must be accessible during normal business hours to an individual performing a compliance inspection. 3. The owner or operator of a construction activity shall not disturb greater than five (5) acres of soil at any one time without prior written authorization from the Department or, in areas under the jurisdiction of a regulated, traditional land use control MS4, the regulated, traditional land use control MS4 (provided the regulated, traditional land use control MS4 is not the owner or operator of the construction activity). At a minimum, the owner or operator must comply with the following requirements in order to be authorized to disturb greater than five (5) acres of soil at any one time: a. The owner or operator shall 15 (Part II.B.3) will be authorized to discharge stormwater from their construction activity in accordance with the following schedule: a. For construction activities that are not subject to the requirements of a regulated, traditional land use control MS4: (i) Five (5) business days from the date the Department receives a complete electronic version of the NOI (eN01) for construction activities with a SWPPP that has been prepared in conformance with the design criteria in the technical standard referenced in Part III.B.1 and the performance criteria in the technical standard referenced in Parts III.B., 2 or 3, for construction activities that require post -construction stormwater management practices pursuant to Part III.C.; or (ii) Sixty (60) business days from the date the Department receives a complete NOI (electronic or paper version) for construction activities with a SWPPP that has not been prepared in conformance with the design criteria in technical standard referenced in Part 111.8.1. or, for construction activities that require post -construction stormwater management practices pursuant to Part III.C., the performance criteria in the technical standard referenced in Parts III.B., 2 or 3, or; (iii) Ten (10) business days from the date the Department receives a complete paper version of the NOI for construction activities with a SWPPP that has been prepared in conformance with the design criteria in the technical standard referenced in Part III.B.1 and the performance criteria in the technical standard referenced in Parts III.B., 2 or 3, for construction activities that require post - construction stormwater management practices pursuant to Part III.C. b. For construction activities that are subject to the requirements of a regulated, traditional land use control MS4: (i) Five (5) business days from the date the Department receives both a complete electronic version of the NOI (eN01) and signed "MS4 SWPPP Acceptance" form, or (ii) Ten (10) business days from the date the Department receives both a complete paper version of the NOI and signed "MS4 SWPPP Acceptance" form. 4. The Department may suspend or deny an owner's or operator's coverage 14 (Part II.C.3.a) have a qualified inspector conduct at least two (2) site inspections in accordance with Part IV.C. of this permit every seven (7) calendar days, for as long as greater than five (5) acres of soil remain disturbed. The two (2) inspections shall be separated by a minimum of two (2) full calendar days. b. In areas where soil disturbance activity has temporarily or permanently ceased, the application of soil stabilization measures must be initiated by the end of the next business day and completed within seven (7) days from the date the current soil disturbance activity ceased. The soil stabilization measures selected shall be in conformance with the technical standard, New York State Standards and Specifications for Erosion and Sediment Control, dated August 2005. c. The owner oroperatorshall prepare a phasing plan that defines maximum disturbed area per phase and shows required cuts and fills. d. The owner or operator shall install any additional site specific practices needed to protect water quality. e. The owner or operator shall include the requirements above in their SWPPP. I In accordance with statute, regulations, and the terms and conditions of this permit, the Department may suspend or revoke an owner's or operator's coverage under this permit at any time if the Department determines that the SWPPP does not meet the permit requirements. Upon a finding of significant non-compliance with the practices described in the SWPPP or violation of this permit, the Department may order an immediate stop to all activity at the site until the non-compliance is remedied. The stop work order shall be in writing, describe the non-compliance in detail, and be sent to the owner or operator. a For construction activities that are subject to the requirements of a regulated, traditional land use control MS4, the owner or operator shall notify the regulated, traditional land use control MS4 in writing of any planned amendments or modifications to the post -construction stormwater management practice component of the SWPPP required by Part III.A. 4. and 5. of this permit. Unless otherwise notified by the regulated, traditional land use control MS4, the owner or operator shall have the SWPPP amendments or modifications reviewed and accepted by the regulated, traditional land use control MS4 prior to commencing construction of the post -construction stormwater management practice 16 (Part II.D) D. Permit Coverage for Discharges Authorized Under GP -0-10-001 1 . Upon renewal of SPDES General Permit for Stormwater Discharges from Construction Activity (Permit No. GP -0-10-001), an owner or operator of a construction activity with coverage under GP -0-10-001, as of the effective date of GP -0-15-002, shall be authorized to discharge in accordance with GP -0-15-002, unless otherwise notified by the Department. An owner or operator may continue to implement the technical/design components of the post -construction stormwater management controls provided that such design was done in conformance with the technical standards in place at the time of initial project authorization. However, they must comply with the other, non -design provisions of GP -0-15-002. E. Change of Owner or Operator (Part III.A.5) When property ownership changes or when there is a change in operational control over the construction plans and specifications, the original owner or operator must notify the new owner or operator, in writing, of the requirement to obtain permit coverage by submitting a NOI with the Department. Once the new owner or operator obtains permit coverage, the original owner or operator shall then submit a completed NOT with the name and permit identification number of the new owner or operator to the Department at the address in Part II.A.1. of this permit. If the original owner or operator maintains ownership of a portion of the construction activity and will disturb soil, they must maintain their coverage under the permit. Permit coverage for the new owner or operator will be effective as of the date the Department receives a complete NOI, provided the original owner or operatorwas not subject to a sixty (60) business day authorization period that has not expired as of the date the Department receives the NOI from the new owner or operator. SWPPP does not meet one or more of the minimum requirements of this permit. The notification shall be in writing and identify the provisions of the SWPPP that require modification. Within fourteen (14) calendar days of such notification, or as otherwise indicated by the Department, the owner or operator shall make the required changes to the SWPPP and submit written notification to the Department that the changes have been made. If the owner or operator does not respond to the Department's comments in the specified time frame, the Department may suspend the owner's or operator's coverage under this permit or require the owner or operator to obtain coverage under an individual SPDES permit in accordance with Part II.C.4. of this permit. Prior to the commencement of construction activity, the owner or operator must identify the contractor(s) and subcontractor(s) that will be responsible for installing, constructing, repairing, replacing, inspecting and maintaining the erosion and sediment control practices included in the SWPPP; and the contractor(s) and subcontractor(s) that will be responsible for constructing the post -construction stormwater management practices included in the SWPPP. The owner or operator shall have each of the contractors and subcontractors identify at least one person from their company that will be responsible for implementation of the SWPPP. This person shall be known as the trained contractor. The owner or operator shall ensure that at least one trained contractor is on site on a daily basis when soil disturbance activities are being performed. The owner or operator shall have each of the contractors and subcontractors identified above sign a copy of the following certification statement below before they commence any construction activity: "I hereby certify under penalty of law that I understand and agree to comply with the terms and conditions of the SWPPP and agree to implement any corrective actions identified by the qualified inspector during a site inspection. I also understand that the owner or operator must comply with the terms and conditions of the most current version of the New York State Pollutant Discharge Elimination System ("SPDES") general permit for stormwater discharges from construction activities and that it is unlawful for any person to cause or contribute to a violation of water quality standards. Furthermore, I am aware that there are significant penalties for submitting false information, that I do not believe to be true, including the possibility of fine and imprisonment for knowing violations" In addition to providing the certification statement above, the certification page must also identify the specific elements of the SWPPP that each contractor and subcontractor will be responsible for and include the name and title of the person providing the signature; the name and title of the 19 (Part III) Part III. STORMWATER POLLUTION PREVENTION PLAN (SWPPP) A. General SWPPP Requirements 1. A SWPPP shall be prepared and implemented by the owner or operator of each construction activity covered by this permit. The SWPPP must document the selection, design, installation, implementation and maintenance of the control measures and practices that will be used to meet the effluent limitations in Part I.B. of this permit and where applicable, the post -construction stormwater management practice requirements in Part I.C. of this permit. The SWPPP shall be prepared prior to the submittal of the NOI. The NOI shall be submitted to the Department prior to the commencement of construction activity. A copy of the completed, final NOI shall be included in the SWPPP. 2 The SWPPP shall describe the erosion and sediment control practices and where required, post -construction stormwater management practices that will be used and/or constructed to reduce the pollutants in stormwater discharges and to assure compliance with the terms and conditions of this permit. In addition, the SWPPP shall identify potential sources of pollution which may reasonably be expected to affect the quality of stormwater discharges. 3. All SWPPPs that require the post -construction stormwater management practice component shall be prepared by a qualified professional that is knowledgeable in the principles and practices of stormwater management and treatment. 4 The owner or operator must keep the SWPPP current so that it at all times accurately documents the erosion and sediment controls practices that are being used or will be used during construction, and all post -construction stormwater management practices that will be constructed on the site. At a minimum, the owner or operator shall amend the SWPPP: a. whenever the current provisions prove to be ineffective in minimizing pollutants in stormwater discharges from the site; b. whenever there is a change in design, construction, or operation at the construction site that has or could have an effect on the discharge of pollutants; and c. to address issues or deficiencies identified during an inspection by the qualified inspector, the Department or other regulatory authority. 5. The Department may notify the owner or operator at any time that the (Part III.A.6) trained contractor responsible for SWPPP implementation; the name, address and telephone number of the contracting firm; the address (or other identifying description) of the site; and the date the certification statement is signed. The owner or operator shall attach the certification statement(s) to the copy of the SWPPP that is maintained at the construction site. If new or additional contractors are hired to implement measures identified in the SWPPP after construction has commenced, they must also sign the certification statement and provide the information listed above. 7. For projects where the Department requests a copy of the SWPPP or inspection reports, the owner or operator shall submit the documents in both electronic (PDF only) and paper format within five (5) business days, unless otherwise notified by the Department. B. Required SWPPP Contents 1 Erosion and sediment control component - All SWPPPs prepared pursuant to this permit shall include erosion and sediment control practices designed in conformance with the technical standard, New York State Standards and Specifications for Erosion and Sediment Control, dated August 2005. Where erosion and sediment control practices are not designed in conformance with the design criteria included in the technical standard, the owner or operator must demonstrate equivalence to the technical standard. At a minimum, the erosion and sediment control component of the SWPPP shall include the following: a. Background information about the scope of the project, including the location, type and size of project; b. A site map/construction drawing(s) for the project, including a general location map. At a minimum, the site map shall show the total site area; all improvements; areas of disturbance; areas that will not be disturbed. existing vegetation; on-site and adjacent off-site surface water(s), flood plain/floodway boundaries; wetlands and drainage patterns that could be affected by the construction activity; existing and final contours ; locations of different soil types with boundaries; material, waste, borrow or equipment storage areas located on adjacent properties; and location(s) of the stormwater discharge(s); c. A description of the soil(s) present at the site, including an identification of the Hydrologic Soil Group (HSG); d. A construction phasing plan and sequence of operations describing the intended order of construction activities, including clearing and grubbing, excavation and grading, utility and infrastructure installation and any other 20 (Part III.B.1.d) activity at the site that results in soil disturbance; e. A description of the minimum erosion and sediment control practices to be installed or implemented for each construction activity that will result in soil disturbance. Include a schedule that identifies the timing of initial placement or implementation of each erosion and sediment control practice and the minimum time frames that each practice should remain in place or be implemented; f. A temporary and permanent soil stabilization plan that meets the requirements of this general permit and the technical standard, New York State Standards and Specifications for Erosion and Sediment Control, dated August 2005, for each stage of the project, including initial land clearing and grubbing to project completion and achievement of final stabilization; g. A site map/construction drawing(s) showing the specific location(s), size(s), and length(s) of each erosion and sediment control practice; h. The dimensions, material specifications, installation details, and operation and maintenance requirements for all erosion and sediment control practices. Include the location and sizing of any temporary sediment basins and structural practices that will be used to divert flows from exposed soils; i. A maintenance inspection schedule for the contractor(s) identified in Part III.A.6. of this permit, to ensure continuous and effective operation of the erosion and sediment control practices. The maintenance inspection schedule shall be in accordance with the requirements in the technical standard, New York State Standards and Specifications for Erosion and Sediment Control, dated August 2005; j. A description of the pollution prevention measures that will be used to control litter, construction chemicals and construction debris from becoming a pollutant source in the stormwater discharges; k. A description and location of any stormwater discharges associated with industrial activity other than construction at the site, including, but not limited to, stormwater discharges from asphalt plants and concrete plants located on the construction site; and I. Identification of any elements of the design that are not in conformance with the design criteria in the technical standard, New York State Standards and Specifications for Erosion and Sediment Control, dated August 2005. Include the reason for the deviation or alternative design 21 (Part 111.B.2.c.iv) that each post -construction stormwater management practice has been designed in conformance with the sizing criteria included in the Design Manual; (v) Identification of any sizing criteria that is not required based on the requirements included in Part I.C. of this permit; and (vi) Identification of any elements of the design that are not in conformance with the performance criteria in the Design Manual. Include the reason(s) for the deviation or alternative design and provide information which demonstrates that the deviation or alternative design is equivalent to the Design Manual; d. Soil testing results and locations (test pits, borings); e. Infiltration test results, when required; and f. An operations and maintenance plan that includes inspection and maintenance schedules and actions to ensure continuous and effective operation of each post -construction stormwater management practice. The plan shall identify the entity that will be responsible for the long term operation and maintenance of each practice. 3. Enhanced Phosphorus Removal Standards - All construction projects identified in Table 2 of Appendix B that are located in the watersheds identified in Appendix C shall prepare a SWPPP that includes post - construction stormwater management practices designed in conformance with the applicable sizing criteria in Part I.C.2. b., c. or d. of this permit and the performance criteria, Enhanced Phosphorus Removal Standards included in the Design Manual. At a minimum, the post -construction stormwater management practice component of the SWPPP shall include items 2.a - 2.f. above. C. Required SWPPP Components by Project Type Unless otherwise notified by the Department, owners or operators of construction activities identified in Table 1 of Appendix B are required to prepare a SWPPP that only includes erosion and sediment control practices designed in conformance with Part III.B.1 of this permit. Owners or operators of the construction activities identified in Table 2 of Appendix B shall prepare a SWPPP that also includes post -construction stormwater management practices designed in conformance with Part III.B.2 or 3 of this permit. (Part III.B.1.1) and provide information which demonstrates that the deviation or alternative design is equivalent to the technical standard. 2 Post -construction stormwater management practice component — The owner or operator of any construction project identified in Table 2 of Appendix B as needing post -construction stormwater management practices shall prepare a SWPPP that includes practices designed in conformance with the applicable sizing criteria in Part I.C.2.a., c. or d. of this permit and the performance criteria in the technical standard, New York State Stormwater Management Design Manual dated January 2015 Where post -construction stormwater management practices are not designed in conformance with the performance criteria in the technical standard, the owner or operator must include in the SWPPP the reason(s) for the deviation or alternative design and provide information which demonstrates that the deviation or alternative design is equivalent to the technical standard. The post -construction stormwater management practice component of the SWPPP shall include the following: a. Identification of all post -construction stormwater management practices to be constructed as part of the project. Include the dimensions, material specifications and installation details for each post -construction stormwater management practice; b. A site map/construction drawing(s) showing the specific location and size of each post -construction stormwater management practice; c. A Stormwater Modeling and Analysis Report that includes: (i) Map(s) showing pre -development conditions, including watershed/subcatchments boundaries, flow paths/routing, and design points; (ii) Map(s) showing post -development conditions, including watershed/subcatchments boundaries, flow paths/routing, design points and post -construction stormwater management practices; (iii) Results of stormwater modeling (i.e. hydrology and hydraulic analysis) for the required storm events. Include supporting calculations (model runs), methodology, and a summary table that compares pre and post -development runoff rates and volumes for the different storm events; (iv) Summary table, with supporting calculations, which demonstrates 22 (Part IV) Part IV. INSPECTION AND MAINTENANCE REQUIREMENTS A. General Construction Site Inspection and Maintenance Requirements 1 . The owner or operator must ensure that all erosion and sediment control practices (including pollution prevention measures) and all post - construction stormwater management practices identified in the SWPPP are inspected and maintained in accordance with Part IV.B. and C. of this permit. 2 The terms of this permit shall not be construed to prohibit the State of New York from exercising any authority pursuant to the ECL, common law or federal law, or prohibit New York State from taking any measures, whether civil or criminal, to prevent violations of the laws of the State of New York, or protect the public health and safety and/or the environment. B. Contractor Maintenance Inspection Requirements 1 . The owner or operator of each construction activity identified in Tables 1 and 2 of Appendix B shall have a trained contractor inspect the erosion and sediment control practices and pollution prevention measures being implemented within the active work area daily to ensure that they are being maintained in effective operating condition at all times. If deficiencies are identified, the contractor shall begin implementing corrective actions within one business day and shall complete the corrective actions in a reasonable time frame. r' For construction sites where soil disturbance activities have been temporarily suspended (e.g. winter shutdown) and temporary stabilization measures have been applied to all disturbed areas, the trained contractor can stop conducting the maintenance inspections. The trained contractor shall begin conducting the maintenance inspections in accordance with Part IV.B.1. of this permit as soon as soil disturbance activities resume. 3. For construction sites where soil disturbance activities have been shut down with partial project completion, the trained contractor can stop conducting the maintenance inspections if all areas disturbed as of the project shutdown date have achieved final stabilization and all post -construction stormwater management practices required for the completed portion of the project have been constructed in conformance with the SWPPP and are operational. C. Qualified Inspector Inspection Requirements 23 24 (Part IV.C) The owner or operator shall have a qualified inspector conduct site inspections in conformance with the following requirements: [Note: The trained contractor identified in Part III.A.6. and IV.B. of this permit cannot conduct the qualified inspector site inspections unless they meet the qualified inspector qualifications included in Appendix A. In order to perform these inspections, the trained contractor would have to be a- - licensed Professional Engineer, - Certified Professional in Erosion and Sediment Control (CPESC), - Registered Landscape Architect, or - someone working under the direct supervision of, and at the same company as, the licensed Professional Engineer or Registered Landscape Architect, provided they have received four (4) hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Department endorsed entity]. 1. A qualified inspector shall conduct site inspections for all construction activities identified in Tables 1 and 2 of Appendix B, with the exception of: a. the construction of a single family residential subdivision with 25% or less impervious cover at total site build -out that involves a soil disturbance of one (1) or more acres of land but less than five (5) acres and is not located in one of the watersheds listed in Appendix C and not directly discharging to one of the 303(d) segments listed in Appendix E; b. the construction of a single family home that involves a soil disturbance of one (1) or more acres of land but less than five (5) acres and is not located in one of the watersheds listed in Appendix C and not directly discharging to one of the 303(d) segments listed in Appendix E; c. construction on agricultural property that involves a soil disturbance of one (1) or more acres of land but less than five (5) acres; and d. construction activities located in the watersheds identified in Appendix D that involve soil disturbances between five thousand (5,000) square feet and one (1) acre of land. `. Unless otherwise notified by the Department, the qualified inspector shall conduct site inspections in accordance with the following timetable: (Part IV.C.2.e) a. For construction sites where soil disturbance activities are on-going, the qualified inspector shall conduct a site inspection at least once every seven (7) calendar days. b. For construction sites where soil disturbance activities are on-going and 25 be separated by a minimum of two (2) full calendar days. 3. At a minimum, the qualified inspectorshall inspect all erosion and sediment control practices and pollution prevention measures to ensure integrity and effectiveness, all post -construction stormwater management practices under construction to ensure that they are constructed in conformance with the SWPPP, all areas of disturbance that have not achieved final stabilization, all points of discharge to natural surface waterbodies located within, or immediately adjacent to, the property boundaries of the construction site, and all points of discharge from the construction site. 4. The qualified inspector shall prepare an inspection report subsequent to each and every inspection. At a minimum, the inspection report shall include and/or address the following: a. Date and time of inspection; b. Name and title of person(s) performing inspection; c. A description of the weather and soil conditions (e.g. dry, wet, saturated) at the time of the inspection; d. A description of the condition of the runoff at all points of discharge from the construction site. This shall include identification of any discharges of sediment from the construction site. Include discharges from conveyance systems (i.e. pipes, culverts, ditches, etc.) and overland flow; e. A description of the condition of all natural surface waterbodies located within, or immediately adjacent to, the property boundaries of the construction site which receive runoff from disturbed areas. This shall include identification of any discharges of sediment to the surface waterbody; f. Identification of all erosion and sediment control practices and pollution prevention measures that need repair or maintenance; g. Identification of all erosion and sediment control practices and pollution prevention measures that were not installed properly or are not functioning as designed and need to be reinstalled or replaced; h. Description and sketch of areas with active soil disturbance activity, areas that have been disturbed but are inactive at the time of the inspection, and areas that have been stabilized (temporary and/or final) since the last inspection; (Part IV.C.2.b) (Part IV.C.4.i) the owner or operator has received authorization in accordance with Part II.C.3 to disturb greater than five (5) acres of soil at any one time, the qualified inspector shall conduct at least two (2) site inspections every seven (7) calendar days. The two (2) inspections shall be separated by a minimum of two (2) full calendar days. c. For construction sites where soil disturbance activities have been temporarily suspended (e.g. winter shutdown) and temporary stabilization measures have been applied to all disturbed areas, the qualified inspector shall conduct a site inspection at least once every thirty (30) calendar days. The owner or operator shall notify the DOW Water (SPDES) Program contact at the Regional Office (see contact information in Appendix F) or, in areas under the jurisdiction of a regulated, traditional land use control MS4, the regulated, traditional land use control MS4 (provided the regulated, traditional land use control MS4 is not the owner or operator of the construction activity) in writing prior to reducing the frequency of inspections. d. For construction sites where soil disturbance activities have been shut down with partial project completion, the qualified inspector can stop conducting inspections if all areas disturbed as of the project shutdown date have achieved final stabilization and all post -construction stormwater management practices required for the completed portion of the project have been constructed in conformance with the SWPPP and are operational. The owner or operator shall notify the DOW Water (SPDES) Program contact at the Regional Office (see contact information in Appendix F) or, in areas under the jurisdiction of a regulated, traditional land use control MS4, the regulated, traditional land use control MS4 (provided the regulated, traditional land use control MS4 is not the owner or operator of the construction activity) in writing prior to the shutdown. If soil disturbance activities are not resumed within 2 years from the date of shutdown, the owner or operator shall have the qualified inspector perform a final inspection and certify that all disturbed areas have achieved final stabilization, and all temporary, structural erosion and sediment control measures have been removed, and that all post -construction stormwater management practices have been constructed in conformance with the SWPPP by signing the "Final Stabilization" and "Post -Construction Stormwater Management Practice" certification statements on the NOT. The owner or operator shall then submit the completed NOT form to the address in Part II.A.1 of this permit. e. For construction sites that directly discharge to one of the 303(d) segments listed in Appendix E or is located in one of the watersheds listed in Appendix C, the qualified inspector shall conduct at least two (2) site inspections every seven (7) calendar days. The two (2) inspections shall 26 Current phase of construction of all post -construction stormwater management practices and identification of all construction that is not in conformance with the SWPPP and technical standards; j. Corrective action(s) that must be taken to install, repair, replace or maintain erosion and sediment control practices and pollution prevention measures; and to correct deficiencies identified with the construction of the post -construction stormwater management practice(s); k. Identification and status of all corrective actions that were required by previous inspection; and I. Digital photographs, with date stamp, that clearly show the condition of all practices that have been identified as needing corrective actions. The qualified inspector shall attach paper color copies of the digital photographs to the inspection report being maintained onsite within seven (7) calendar days of the date of the inspection. The qualified inspector shall also take digital photographs, with date stamp, that clearly show the condition of the practice(s) after the corrective action has been completed. The qualified inspector shall attach paper color copies of the digital photographs to the inspection report that documents the completion of the corrective action work within seven (7) calendar days of that inspection. :5. Within one business day of the completion of an inspection, the qualified inspector shall notify the owner or operator and appropriate contractor or subcontractor identified in Part III.A.6. of this permit of any corrective actions that need to be taken. The contractor or subcontractor shall begin implementing the corrective actions within one business day of this notification and shall complete the corrective actions in a reasonable time frame. 6 All inspection reports shall be signed by the qualified inspector. Pursuant to Part II.C.2. of this permit, the inspection reports shall be maintained on site with the SWPPP. Part V. TERMINATION OF PERMIT COVERAGE A. Termination of Permit Coverage 1. An owner or operator that is eligible to terminate coverage under this permit must submit a completed NOT form to the address in Part II.A.1 of this permit. The NOT form shall be one which is associated with this permit, signed in accordance with Part VII.H of this permit. 27 28 (Part V.A.2) }° An owner or operator may terminate coverage when one or more the following conditions have been met: a. Total project completion - All construction activity identified in the SWPPP has been completed; and all areas of disturbance have achieved final stabilization; and all temporary, structural erosion and sediment control measures have been removed; and all post -construction stormwater management practices have been constructed in conformance with the SWPPP and are operational; b. Planned shutdown with partial project completion - All soil disturbance activities have ceased; and all areas disturbed as of the project shutdown date have achieved final stabilization; and all temporary, structural erosion and sediment control measures have been removed; and all post - construction stormwater management practices required for the completed portion of the project have been constructed in conformance with the SWPPP and are operational; c. A new owner or operator has obtained coverage under this permit in accordance with Part II.E. of this permit. d. The owner or operator obtains coverage under an alternative SPDES general permit or an individual SPDES permit. �. For construction activities meeting subdivision 2a. or 2b. of this Part, the owner or operator shall have the qualified inspector perform a final site inspection prior to submitting the NOT. The qualified inspector shall, by signing the "Final Stabilization" and "Post -Construction Stormwater Management Practice certification statements on the NOT, certify that all the requirements in Part V.A.2.a. or b. of this permit have been achieved. 4. For construction activities that are subject to the requirements of a regulated, traditional land use control MS4 and meet subdivision 2a. or 2b. of this Part, the owner or operator shall have the regulated, traditional land use control MS4 sign the "MS4 Acceptance" statement on the NOT in accordance with the requirements in Part VII.H. of this permit. The regulated, traditional land use control MS4 official, by signing this statement, has determined that it is acceptable for the owner or operator to submit the NOT in accordance with the requirements of this Part. The regulated, traditional land use control MS4 can make this determination by performing a final site inspection themselves or by accepting the qualified inspector's final site inspection certification(s) required in Part V.A.3. of this permit. 29 (Part VII) Part VII. STANDARD PERMIT CONDITIONS A. Duty to Comply The owner or operator must comply with all conditions of this permit. All contractors and subcontractors associated with the project must comply with the terms of the SWPPP. Any non-compliance with this permit constitutes a violation of the Clean Water Act (CWA) and the ECL and is grounds for an enforcement action against the owner or operator and/or the contractor/subcontractor; permit revocation, suspension or modification; or denial of a permit renewal application. Upon a finding of significant non-compliance with this permit or the applicable SWPPP, the Department may order an immediate stop to all construction activity at the site until the non-compliance is remedied. The stop work order shall be in writing, shall describe the non-compliance in detail, and shall be sent to the owner or operator. If any human remains or archaeological remains are encountered during excavation, the owner or operator must immediately cease, or cause to cease, all construction activity in the area of the remains and notify the appropriate Regional Water Engineer (RWE). Construction activity shall not resume until written permission to do so has been received from the RWE. B. Continuation of the Expired General Permit This permit expires five (5) years from the effective date. If a new general permit is not issued prior to the expiration of this general permit, an owner or operator with coverage under this permit may continue to operate and discharge in accordance with the terms and conditions of this general permit, if it is extended pursuant to the State Administrative Procedure Act and 6 NYCRR Part 621, until a new general permit is issued. C. Enforcement Failure of the owner or operator, its contractors, subcontractors, agents and/or assigns to strictly adhere to any of the permit requirements contained herein shall constitute a violation of this permit. There are substantial criminal, civil, and administrative penalties associated with violating the provisions of this permit. Fines of up to $37,500 per day for each violation and imprisonment for up to fifteen (15) years may be assessed depending upon the nature and degree of the offense. D. Need to Halt or Reduce Activity Not a Defense It shall not be a defense for an owner or operator in an enforcement action that it would have been necessary to halt or reduce the construction activity in order to maintain compliance with the conditions of this permit. (Part V.A.5) 5. For construction activities that require post -construction stormwater management practices and meet subdivision 2a. of this Part, the owner or operator must, prior to submitting the NOT, ensure one of the following: a. the post -construction stormwater management practice(s) and any right- of-way(s) needed to maintain such practice(s) have been deeded to the municipality in which the practice(s) is located, b. an executed maintenance agreement is in place with the municipality that will maintain the post -construction stormwater management practice(s), c. for post -construction stormwater management practices that are privately owned, the owner or operator has a mechanism in place that requires operation and maintenance of the practice(s) in accordance with the operation and maintenance plan, such as a deed covenant in the owner or operator's deed of record, d. for post -construction stormwater management practices that are owned by a public or private institution (e.g. school, university, hospital), government agency or authority, or public utility; the owner or operator has policy and procedures in place that ensures operation and maintenance of the practices in accordance with the operation and maintenance plan. Part VI. REPORTING AND RETENTION OF RECORDS A. Record Retention The owner or operator shall retain a copy of the NOI, NOI Acknowledgment Letter, SWPPP, MS4 SWPPP Acceptance form and any inspection reports that were prepared in conjunction with this permit for a period of at least five (5) years from the date that the Department receives a complete NOT submitted in accordance with Part V. of this general permit. B. Addresses With the exception of the NOI, NOT, and MS4 SWPPP Acceptance form (which must be submitted to the address referenced in Part II.A.1 of this permit), all written correspondence requested by the Department, including individual permit applications, shall be sent to the address of the appropriate DOW Water (SPDES) Program contact at the Regional Office listed in Appendix F. (Part VILE) E. Duty to Mitigate The owner or operator and its contractors and subcontractors shall take all reasonable steps to minimize or prevent any discharge in violation of this permit which has a reasonable likelihood of adversely affecting human health or the environment. F. Duty to Provide Information The owner or operator shall furnish to the Department, within a reasonable specified time period of a written request, all documentation necessary to demonstrate eligibility and any information to determine compliance with this permit or to determine whether cause exists for modifying or revoking this permit, or suspending or denying coverage under this permit, in accordance with the terms and conditions of this permit. The NOI, SWPPP and inspection reports required by this permit are public documents that the owner or operator must make available for review and copying by any person within five (5) business days of the owner or operator receiving a written request by any such person to review these documents. Copying of documents will be done at the requester's expense. G. Other Information When the owner or operator becomes aware that they failed to submit any relevant facts, or submitted incorrect information in the NOI or in any of the documents required by this permit , or have made substantive revisions to the SWPPP (e.g. the scope of the project changes significantly, the type of post -construction stormwater management practice(s) changes, there is a reduction in the sizing of the post - construction stormwater management practice, or there is an increase in the disturbance area or impervious area), which were not reflected in the original NOI submitted to the Department, they shall promptly submit such facts or information to the Department using the contact information in Part II.A. of this permit. Failure of the owner or operator to correct or supplement any relevant facts within five (5) business days of becoming aware of the deficiency shall constitute a violation of this permit. H. Signatory Requirements 1. All NOls and NOTs shall be signed as follows: a. For a corporation these forms shall be signed by a responsible corporate officer. For the purpose of this section, a responsible corporate officer means: (i) a president, secretary, treasurer, or vice-president of the (Part VII.H.1.a.i) corporation in charge of a principal business function, or any other person who performs similar policy or decision-making functions for the corporation; or (ii) the manager of one or more manufacturing, production or operating facilities, provided the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmental compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures; b. For a partnership or sole proprietorship these forms shall be signed by a general partner or the proprietor, respectively; or c. For a municipality, State, Federal, or other public agency these forms shall be signed by either a principal executive officer or ranking elected official. For purposes of this section, a principal executive officer of a Federal agency includes: the chief executive officer of the agency, or (ii) a senior executive officer having responsibility for the overall operations of a principal geographic unit of the agency (e.g., Regional Administrators of EPA). ' The SWPPP and other information requested by the Department shall be signed by a person described in Part VII.H.1. of this permit or by a duly authorized representative of that person. A person is a duly authorized representative only if: (Part VII.K.1) a. The authorization is made in writing by a person described in Part VII.H.1. of this permit; b. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility or activity, such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the company. (A duly authorized representative may thus be either a named 33 discharge under this general permit shall be terminated. Applications must be submitted to the appropriate Permit Administrator at the Regional Office. The Department may grant additional time upon demonstration, to the satisfaction of the Department, that additional time to apply for an alternative authorization is necessary or where the Department has not provided a permit determination in accordance with Part 621 of this Title. 2 When an individual SPDES permit is issued to a discharger authorized to discharge under a general SPDES permit for the same discharge(s), the general permit authorization for outfalls authorized under the individual SPDES permit is automatically terminated on the effective date of the individual permit unless termination is earlier in accordance with 6 NYCRR Part 750. L. Proper Operation and Maintenance The owner or operator shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the owneroroperatorto achieve compliance with the conditions of this permit and with the requirements of the SWPPP. M. Inspection and Entry The owner or operator shall allow an authorized representative of the Department, EPA, applicable county health department, or, in the case of a construction site which discharges through an MS4, an authorized representative of the MS4 receiving the discharge, upon the presentation of credentials and other documents as may be required by law, to: 1. Enter upon the owner's or operator's premises where a regulated facility or activity is located or conducted or where records must be kept under the conditions of this permit; Have access to and copy at reasonable times, any records that must be kept under the conditions of this permit; and 3. Inspect at reasonable times any facilities or equipment (including monitoring and control equipment), practices or operations regulated or required by this permit. 4. Sample or monitor at reasonable times, for purposes of assuring permit compliance or as otherwise authorized by the Act or ECL, any substances or parameters at any location. (Part VII.H.2.b) individual or any individual occupying a named position) and, c. The written authorization shall include the name, title and signature of the authorized representative and be attached to the SWPPP. 3. All inspection reports shall be signed by the qualified inspector that performs the inspection. 4. The MS4 SWPPP Acceptance form shall be signed by the principal executive officer or ranking elected official from the regulated, traditional land use control MS4, or by a duly authorized representative of that person. It shall constitute a permit violation if an incorrect and/or improper signatory authorizes any required forms, SWPPP and/or inspection reports. I. Property Rights The issuance of this permit does not convey any property rights of any sort, nor any exclusive privileges, nor does it authorize any injury to private property nor any invasion of personal rights, nor any infringement of Federal, State or local laws or regulations. Owners or operators must obtain any applicable conveyances, easements, licenses and/or access to real property prior to commencing construction activity. J. Severability The provisions of this permit are severable, and if any provision of this permit, or the application of any provision of this permit to any circumstance, is held invalid, the application of such provision to other circumstances, and the remainder of this permit shall not be affected thereby. K. Requirement to Obtain Coverage Under an Alternative Permit 1. The Department may require any owner or operator authorized by this permit to apply for and/or obtain either an individual SPDES permit or another SPDES general permit. When the Department requires any discharger authorized by a general permit to apply for an individual SPDES permit, it shall notify the discharger in writing that a permit application is required. This notice shall include a brief statement of the reasons for this decision, an application form, a statement setting a time frame for the owner or operator to file the application for an individual SPDES permit, and a deadline, not sooner than 180 days from owner or operator receipt of the notification letter, whereby the authorization to 34 (Part VII.N) N. Permit Actions This permit may, at any time, be modified, suspended, revoked, or renewed by the Department in accordance with 6 NYCRR Part 621. The filing of a request by the owner or operator for a permit modification, revocation and reissuance, termination, a notification of planned changes or anticipated noncompliance does not limit, diminish and/or stay compliance with any terms of this permit. O. Definitions Definitions of key terms are included in Appendix A of this permit. P. Re -Opener Clause 1. If there is evidence indicating potential or realized impacts on water quality due to any stormwater discharge associated with construction activity covered by this permit, the owner or operator of such discharge may be required to obtain an individual permit or alternative general permit in accordance with Part VII.K. of this permit or the permit may be modified to include different limitations and/or requirements. f Any Department initiated permit modification, suspension or revocation will be conducted in accordance with 6 NYCRR Part 621, 6 NYCRR 750-1.18, and 6 NYCRR 750-1.20. Q. Penalties for Falsification of Forms and Reports In accordance with 6NYCRR Part 750-2.4 and 750-2.5, any person who knowingly makes any false material statement, representation, or certification in any application, record, report or other document filed or required to be maintained under this permit, including reports of compliance or noncompliance shall, upon conviction, be punished in accordance with ECL §71-1933 and or Articles 175 and 210 of the New York State Penal Law. R. Other Permits Nothing in this permit relieves the owner or operator from a requirement to obtain any other permits required by law. 35 36 APPENDIX A Definitions Alter Hydrology from Pre to Post -Development Conditions - means the post - development peak flow rate(s) has increased by more than 5% of the pre -developed condition for the design storm of interest (e.g. 10 yr and 100 yr). Combined Sewer - means a sewer that is designed to collect and convey both "sewage" and "stormwater". Commence (Commencement of) Construction Activities - means the initial disturbance of soils associated with clearing, grading or excavation activities; or other construction related activities that disturb or expose soils such as demolition, stockpiling of fill material, and the initial installation of erosion and sediment control practices required in the SWPPP. See definition for "Construction Activity(ies)" also. Construction Activity(ies) - means any clearing, grading, excavation, filling, demolition or stockpiling activities that result in soil disturbance. Clearing activities can include, but are not limited to, logging equipment operation, the cutting and skidding of trees, stump removal and/or brush root removal. Construction activity does not include routine maintenance that is performed to maintain the original line and grade, hydraulic capacity, or original purpose of a facility. Direct Discharge (to a specific surface waterbody) - means that runoff flows from a construction site by overland flow and the first point of discharge is the specific surface waterbody, or runoff flows from a construction site to a separate storm sewer system and the first point of discharge from the separate storm sewer system is the specific surface waterbody. Discharge(s) - means any addition of any pollutant to waters of the State through an outlet or point source. Environmental Conservation Law (ECL) - means chapter 43-B of the Consolidated Laws of the State of New York, entitled the Environmental Conservation Law. Equivalent (Equivalence) — means that the practice or measure meets all the performance, longevity, maintenance, and safety objectives of the technical standard and will provide an equal or greater degree of water quality protection. Final Stabilization - means that all soil disturbance activities have ceased and a uniform, perennial vegetative cover with a density of eighty (80) percent over the entire pervious surface has been established; or other equivalent stabilization measures, such as permanent landscape mulches, rock rip -rap or washed/crushed stone have been applied ditches, man-made channels, or storm drains): (i) Owned or operated by a State, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law) having jurisdiction over disposal of sewage, industrial wastes, stormwater, or other wastes, including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated and approved management agency under section 208 of the CWA that discharges to surface waters of the State, (ii) Designed or used for collecting or conveying stormwater; (iii) Which is not a combined sewer, and (iv) Which is not part of a Publicly Owned Treatment Works (POTW) as defined at 40 CFR 122.2. National Pollutant Discharge Elimination System (NPDES) - means the national system for the issuance of wastewater and stormwater permits under the Federal Water Pollution Control Act (Clean Water Act). New Development — means any land disturbance that does not meet the definition of Redevelopment Activity included in this appendix. NOI Acknowledgment Letter - means the letter that the Department sends to an owner or operator to acknowledge the Department's receipt and acceptance of a complete Notice of Intent. This letter documents the owner's or operator's authorization to discharge in accordance with the general permit for stormwater discharges from construction activity. Owner or Operator - means the person, persons or legal entity which owns or leases the property on which the construction activity is occurring; and/or an entity that has operational control over the construction plans and specifications, including the ability to make modifications to the plans and specifications. Performance Criteria — means the design criteria listed under the "Required Elements" sections in Chapters 5, 6 and 10 of the technical standard, New York State Stormwater Management Design Manual, dated January 2015. It does not include the Sizing Criteria (i.e. WQv, RRv, Cpv, Qp and Qf ) in Part I.C.2. of the permit. Pollutant - means dredged spoil, filter backwash, solid waste, incinerator residue, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand and industrial, municipal, agricultural waste and ballast discharged into water; which may cause or might reasonably be expected to cause pollution of the waters of the state in contravention of the standards or guidance values adopted as provided in 6 NYCRR Parts 700 et seq . on all disturbed areas that are not covered by permanent structures, concrete or pavement. General SPDES permit - means a SPDES permit issued pursuant to 6 NYCRR Part 750 1.21 and Section 70-0117 of the ECL authorizing a category of discharges. Groundwater(s) - means waters in the saturated zone. The saturated zone is a subsurface zone in which all the interstices are filled with water under pressure greater than that of the atmosphere. Although the zone may contain gas-filled interstices or interstices filled with fluids other than water, it is still considered saturated. Historic Property — means any building, structure, site, object or district that is listed on the State or National Registers of Historic Places or is determined to be eligible for listing on the State or National Registers of Historic Places. Impervious Area (Cover) - means all impermeable surfaces that cannot effectively infiltrate rainfall. This includes paved, concrete and gravel surfaces (i.e. parking lots, driveways, roads, runways and sidewalks); building rooftops and miscellaneous impermeable structures such as patios, pools, and sheds. Infeasible — means not technologically possible, or not economically practicable and achievable in light of best industry practices. Larger Common Plan of Development or Sale - means a contiguous area where multiple separate and distinct construction activities are occurring, or will occur, under one plan. The term "plan" in "larger common plan of development or sale" is broadly defined as any announcement or piece of documentation (including a sign, public notice or hearing, marketing plan, advertisement, drawing, permit application, State Environmental Quality Review Act (SEQRA) environmental assessment form or other documents, zoning request, computer design, etc.) or physical demarcation (including boundary signs, lot stakes, surveyor markings, etc.) indicating that construction activities may occur on a specific plot. For discrete construction projects that are located within a larger common plan of development or sale that are at least 1/4 mile apart, each project can be treated as a separate plan of development or sale provided any interconnecting road, pipeline or utility project that is part of the same "common plan" is not concurrently being disturbed. Minimize — means reduce and/or eliminate to the extent achievable using control measures (including best management practices) that are technologically available and economically practicable and achievable in light of best industry practices. Municipal Separate Storm Sewer (MS4) - a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, Qualified Inspector - means a person that is knowledgeable in the principles and practices of erosion and sediment control, such as a licensed Professional Engineer, Certified Professional in Erosion and Sediment Control (CPESC), Registered Landscape Architect, or other Department endorsed individual(s). It can also mean someone working under the direct supervision of, and at the same company as, the licensed Professional Engineer or Registered Landscape Architect, provided that person has training in the principles and practices of erosion and sediment control. Training in the principles and practices of erosion and sediment control means that the individual working under the direct supervision of the licensed Professional Engineer or Registered Landscape Architect has received four (4) hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Department endorsed entity. After receiving the initial training, the individual working under the direct supervision of the licensed Professional Engineer or Registered Landscape Architect shall receive four (4) hours of training every three (3) years. It can also mean a person that meets the Qualified Professional qualifications in addition to the Qualified Inspector qualifications. Note: Inspections of any post -construction stormwater management practices that include structural components, such as a dam for an impoundment, shall be performed by a licensed Professional Engineer. Qualified Professional - means a person that is knowledgeable in the principles and practices of stormwater management and treatment, such as a licensed Professional Engineer, Registered Landscape Architect or other Department endorsed individual(s). Individuals preparing SWPPPs that require the post -construction stormwater management practice component must have an understanding of the principles of hydrology, water quality management practice design, water quantity control design, and, in many cases, the principles of hydraulics. All components of the SWPPP that involve the practice of engineering, as defined by the NYS Education Law (see Article 145), shall be prepared by, or under the direct supervision of, a professional engineer licensed to practice in the State of New York.. Redevelopment Activity(ies) — means the disturbance and reconstruction of existing impervious area, including impervious areas that were removed from a project site within five (5) years of preliminary project plan submission to the local government (i.e. site plan, subdivision, etc.). Regulated, Traditional Land Use Control MS4 - means a city, town or village with land use control authority that is required to gain coverage under New York State DEC's SPDES General Permit For Stormwater Discharges from Municipal Separate Stormwater Sewer Systems (MS4s). Routine Maintenance Activity - means construction activity that is performed to maintain the original line and grade, hydraulic capacity, or original purpose of a facility, including, but not limited to- - Re -grading of gravel roads or parking lots, - Stream bank restoration projects (does not include the placement of spoil material), - Cleaning and shaping of existing roadside ditches and culverts that maintains the approximate original line and grade, and hydraulic capacity of the ditch, - Cleaning and shaping of existing roadside ditches that does not maintain the approximate original grade, hydraulic capacity and purpose of the ditch if the changes to the line and grade, hydraulic capacity or purpose of the ditch are installed to improve water quality and quantity controls (e.g. installing grass lined ditch), - Placement of aggregate shoulder backing that makes the transition between the road shoulder and the ditch or embankment, - Full depth milling and filling of existing asphalt pavements, replacement of concrete pavement slabs, and similar work that does not expose soil or disturb the bottom six (6) inches of subbase material, - Long-term use of equipment storage areas at or near highway maintenance facilities, - Removal of sediment from the edge of the highway to restore a previously existing sheet -flow drainage connection from the highway surface to the highway ditch or embankment, - Existing use of Canal Corp owned upland disposal sites for the canal, and - Replacement of curbs, gutters, sidewalks and guide rail posts. Site limitations — means site conditions that prevent the use of an infiltration technique and or infiltration of the total WQv. Typical site limitations include: seasonal high groundwater, shallow depth to bedrock, and soils with an infiltration rate less than 0.5 inches/hour. The existence of site limitations shall be confirmed and documented using actual field testing (i.e. test pits, soil borings, and infiltration test) or using information from the most current United States Department of Agriculture (USDA) Soil Survey for the County where the project is located. Sizing Criteria — means the criteria included in Part I.C.2 of the permit that are used to size post -construction stormwater management control practices. The criteria include; Water Quality Volume (WQv), Runoff Reduction Volume (RRv), Channel Protection Volume (Cpv), Overbank Flood (Qp), and Extreme Flood (Qf). State Pollutant Discharge Elimination System (SPDES) - means the system established pursuant to Article 17 of the ECL and 6 NYCRR Part 750 for issuance of permits authorizing discharges to the waters of the state. Steep Slope — means land area with a Soil Slope Phase that is identified as an E or F, or 621 of the Environmental Conservation Law (ECL), Article 70. Water Quality Standard - means such measures of purity or quality for any waters in relation to their reasonable and necessary use as promulgated in 6 NYCRR Part 700 et seq. the map unit name is inclusive of 25% or greater slope, on the United States Department of Agriculture ("USDA") Soil Survey for the County where the disturbance will occur. Surface Waters of the State - shall be construed to include lakes, bays, sounds, ponds, impounding reservoirs, springs, rivers, streams, creeks, estuaries, marshes, inlets, canals, the Atlantic ocean within the territorial seas of the state of New York and all other bodies of surface water, natural or artificial, inland or coastal, fresh or salt, public or private (except those private waters that do not combine or effect a junction with natural surface waters), which are wholly or partially within or bordering the state or within its jurisdiction. Waters of the state are further defined in 6 NYCRR Parts 800 to 941. Temporarily Ceased — means that an existing disturbed area will not be disturbed again within 14 calendar days of the previous soil disturbance. Temporary Stabilization - means that exposed soil has been covered with material(s) as set forth in the technical standard, New York Standards and Specifications for Erosion and Sediment Control, to prevent the exposed soil from eroding. The materials can include, but are not limited to, mulch, seed and mulch, and erosion control mats (e.g. jute twisted yarn, excelsior wood fiber mats). Total Maximum Daily Loads (TMDLs) - A TMDL is the sum of the allowable loads of a single pollutant from all contributing point and nonpoint sources. It is a calculation of the maximum amount of a pollutant that a waterbody can receive on a daily basis and still meet water quality standards, and an allocation of that amount to the pollutant's sources. A TMDL stipulates wasteload allocations (WLAs) for point source discharges, load allocations (LAS) for nonpoint sources, and a margin of safety (MOS). Trained Contractor - means an employee from the contracting (construction) company, identified in Part III.A.6., that has received four (4) hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Department endorsed entity. After receiving the initial training, the trained contractor shall receive four (4) hours of training every three (3) years. It can also mean an employee from the contracting (construction) company, identified in Part I II.A.6., that meets the qualified inspector qualifications (e.g. licensed Professional Engineer, Certified Professional in Erosion and Sediment Control (CPESC), Registered Landscape Architect, or someone working under the direct supervision of, and at the same company as, the licensed Professional Engineer or Registered Landscape Architect, provided they have received four (4) hours of Department endorsed training in proper erosion and sediment control principles from a Soil and Water Conservation District, or other Department endorsed entity). The trained contractor is responsible for the day to day implementation of the SWPPP. Uniform Procedures Act (UPA) Permit - means a permit required under 6 NYCRR Part 42 APPENDIX B Required SWPPP Components by Project Type Table 1 CONSTRUCTION ACTIVITIES THAT REQUIRE THE PREPARATION OF A SWPPP THAT ONLY INCLUDES EROSION AND SEDIMENT CONTROLS The following construction activities that involve soil disturbances of one (1) or more acres of land, but less than five (5) acres: • Single family home not located in one of the watersheds listed in Appendix C or not directly discharging to one of the 303(d) segments listed in Appendix E • Single family residential subdivisions with 25% or less impervious cover at total site build -out and not located in one of the watersheds listed in Appendix C and not directly discharging to one of the 303(d) segments listed in Appendix E • Construction of a barn or other agricultural building, silo, stock yard or pen. The following construction activities that involve soil disturbances of one (1) or more acres of land: • Installation of underground, linear utilities; such as gas lines, fiber-optic cable, cable TV, electric, telephone, sewer mains, and water mains • Environmental enhancement projects, such as wetland mitigation projects, stormwater retrofits and stream restoration projects • Bike paths and trails • Sidewalk construction projects that are not part of a road/ highway construction or reconstruction project • Slope stabilization projects • Slope flattening that changes the grade of the site, but does not significantly change the runoff characteristics • Spoil areas that will be covered with vegetation • Land clearing and grading for the purposes of creating vegetated open space (i.e. recreational parks, lawns, meadows, fields), excluding projects that alter hydrology from pre to post development conditions • Athletic fields (natural grass) that do not include the construction or reconstruction of impervious area and do not alter hydrology from pre to post development conditions • Demolition project where vegetation will be established and no redevelopment is planned • Overhead electric transmission line project that does not include the construction of permanent access roads or parking areas surfaced with impervious cover • Structural practices as identified in Table II in the "Agricultural Management Practices Catalog for Nonpoint Source Pollution in New York State", excluding projects that involve soil disturbances of less than five acres and construction activities that include the construction or reconstruction of impervious area The following construction activities that involve soil disturbances between five thousand (5000) square feet and one (1) acre of land: All construction activities located in the watersheds identified in Appendix D that involve soil disturbances between five thousand (5,000) square feet and one (1) acre of land. 43 44 Table 2 CONSTRUCTION ACTIVITIES THAT REQUIRE THE PREPARATION OF A SWPPP THAT INCLUDES POST -CONSTRUCTION STORMWATER MANAGEMENT PRACTICES The following construction activities that involve soil disturbances of one (1) or more acres of land: • Single family home located in one of the watersheds listed in Appendix C or directly discharging to one of the 303(d) segments listed in Appendix E • Single family residential subdivisions located in one of the watersheds listed in Appendix C or directly discharging to one of the 303(d) segments listed in Appendix E • Single family residential subdivisions that involve soil disturbances of between one (1) and five (5) acres of land with greater than 25% impervious cover at total site build -out • Single family residential subdivisions that involve soil disturbances of five (5) or more acres of land, and single family residential subdivisions that involve soil disturbances of less than five (5) acres that are part of a larger common plan of development or sale that will ultimately disturb five or more acres of land • Multi -family residential developments; includes townhomes, condominiums, senior housing complexes, apartment complexes, and mobile home parks • Airports • Amusement parks • Campgrounds • Cemeteries that include the construction or reconstruction of impervious area (>5% of disturbed area) or alter the hydrology from pre to post development conditions • Commercial developments • Churches and other places of worship • Construction of a barn or other agricultural building(e.g. silo) and structural practices as identified in Table II in the "Agricultural Management Practices Catalog for Nonpoint Source Pollution in New York State" that include the construction or reconstruction of impervious area, excluding projects that involve soil disturbances of less than five acres. • Golf courses • Institutional, includes hospitals, prisons, schools and colleges • Industrial facilities, includes industrial parks • Landfills • Municipal facilities; includes highway garages, transfer stations, office buildings, POTW's and water treatment plants • Office complexes • Sports complexes • Racetracks, includes racetracks with earthen (dirt) surface • Road construction or reconstruction • Parking lot construction or reconstruction • Athletic fields (natural grass) that include the construction or reconstruction of impervious area (>5% of disturbed area) or alter the hydrology from pre to post development conditions • Athletic fields with artificial turf • Permanent access roads, parking areas, substations, compressor stations and well drilling pads, surfaced with impervious cover, and constructed as part of an over -head electric transmission line project , wind -power project, cell tower project, oil or gas well drilling project, sewer or water main project or other linear utility project • All other construction activities that include the construction or reconstruction of impervious area or alter the hydrology from pre to post development conditions, and are not listed in Table 1 45 Figure 1 - New York City Watershed East of the Hudson EEKIVIAN EAST FISHKILL PAWL ING � d { y ATTERSO N , NT SOUTHEAST o PUT AM VAL L r-+ B&�WSTER CARMEL � F�TH SAI.E�I S�?hdEFS ..Y RKTOW EDFO:RD M UN K GO W CA.9TLE !- RTH CAS: M. U LEASANT HA SON E Old al ecshe�d APPENDIX C Watersheds Where Enhanced Phosphorus Removal Standards Are Required Watersheds where owners or operators of construction activities identified in Table 2 of Appendix B must prepare a SWPPP that includes post -construction stormwater management practices designed in conformance with the Enhanced Phosphorus Removal Standards included in the technical standard, New York State Stormwater Management Design Manual ("Design Manual"). • Entire New York City Watershed located east of the Hudson River - Figure 1 • Onondaga Lake Watershed - Figure 2 • Greenwood Lake Watershed -Figure 3 • Oscawana Lake Watershed — Figure 4 • Kinderhook Lake Watershed — Figure 5 46 Figure 2 - Onondaga Lake Watershed 47 48 Figure 3 - Greenwood Lake Watershed WARWICK a EE WO: EKE Phosphoxus Walarshed 49 �.... .....y.,, ... ..1 .......� �... �..p �....... [] 9 L 4 MB Kinderhook Lake Watershed Figure 4 - Oscawana Lake Watershed Ia:II11 1011WI,1l KENT VALLEY CARMEL u Phosphorus Mle'rsrte;l 50 APPENDIX D Watersheds where owners or operators of construction activities that involve soil disturbances between five thousand (5000) square feet and one (1) acre of land must obtain coverage under this permit. Entire New York City Watershed that is located east of the Hudson River - See Figure 1 in Appendix C 51 52 APPENDIX E List of 303(d) segments impaired by pollutants related to construction activity (e.g. silt, sediment or nutrients). Owners or operators of single family home and single family residential subdivisions with 25% or less total impervious cover at total site build -out that involve soil disturbances of one or more acres of land, but less than 5 acres, and directly discharge to one of the listed segments below shall prepare a SWPPP that includes post -construction stormwater management practices designed in conformance with the New York State Stormwater Management Design Manual ("Design Manual"), dated January 2015. COUNTY WATERBODY COUNTY WATERBODY Albany Ann Lee (Shakers) Pond, Stump Pond Greene Sleepy Hollow Lake Albany Basic Creek Reservoir Herkimer Steele Creek tribs Allegheny Amity Lake, Saunders Pond Kings Hendrix Creek Bronx Van Cortlandt Lake Lewis Mill Creek/South Branch and tribs Broome Whitney Point Lake/Reservoir Livingston Conesus Lake Broome Fly Pond, Deer Lake Livingston Jaycox Creek and tribs Broome Minor Tribs to Lower Susquehanna Livingston Mill Creek and minor tribs BROOME, CAYUGA, CHENANGO, CORTLAND, MADISON, ONONDAGA, OSWEGO, TIOGA AND TOMPKINS (north) Livingston Bradner Creek and tribs Cattaraugus Allegheny River/Reservoir Livingston Christie Creek and tribs Cattaraugus Case Lake Monroe Lake Ontario Shoreline, Western Cattaraugus Linlyco/Club Pond Monroe Mill Creek/Blue Pond Outlet and tribs Cayuga Duck Lake Monroe Rochester Embayment - East Chautauqua Chautauqua Lake, North Monroe Rochester Embayment - West Chautauqua Chautauqua Lake, South Monroe Unnamed Trib to Honeoye Creek Chautauqua Bear Lake Monroe Genesee River, Lower, Main Stem Chautauqua Chadakoin River and tribs Monroe Genesee River, Middle, Main Stem Chautauqua Lower Cassadaga Lake Monroe Black Creek, Lower, and minor tribs Chautauqua Middle Cassadaga Lake Monroe Buck Pond Chautauqua Findley Lake Monroe Long Pond Clinton Great Chazy River, Lower, Main Stem Monroe Cranberry Pond Columbia Kinderhook Lake Monroe Mill Creek and tribs Columbia Robinson Pond Monroe Shipbuilders Creek and tribs Dutchess Hillside Lake Monroe Minor tribs to Irondequoit Bay Dutchess Wappinger Lakes Monroe Thomas Creek/White Brook and tribs Dutchess Fall Kill and tribs Nassau Glen Cove Creek, Lower, and tribs Erie Green Lake Nassau LI Tribs (fresh) to East Bay Erie Scajaquada Creek, Lower, and tribs Nassau East Meadow Brook, Upper, and tribs Erie Scajaquada Creek, Middle, and tribs Nassau Hempstead Bay Erie Scajaquada Creek, Upper, and tribs Nassau Hempstead Lake Erie Rush Creek and tribs Nassau Grant Park Pond Erie Ellicott Creek, Lower, and tribs Nassau Beaver Lake Erie Beeman Creek and tribs Nassau Camaans Pond Erie Murder Creek, Lower, and tribs Nassau Halls Pond Erie South Branch Smoke Cr, Lower, and Nassau LI Tidal Tribs to Hempstead Bay Westchester tribs Nassau Massapequa Creek and tribs Erie Little Sister Creek, Lower, and tribs Nassau Reynolds Channel, east Essex Lake George (primary county: Warren) Nassau Reynolds Channel, west Genesee Black Creek, Upper, and minor tribs Nassau Silver Lake, Lofts Pond Genesee Tonawanda Creek, Middle, Main Stem Nassau Woodmere Channel Genesee Oak Orchard Creek, Upper, and tribs Niagara Hyde Park Lake Genesee Bowen Brook and tribs Niagara Lake Ontario Shoreline, Western Genesee Bigelow Creek and tribs Niagara Bergholtz Creek and tribs Genesee Black Creek, Middle, and minor tribs Oneida Ballou, Nail Creeks Genesee LeRoy Reservoir Onondaga Ley Creek and tribs Greene Schoharie Reservoir Onondaga Onondaga Creek, Lower and tribs APPENDIX F LIST OF NYS DEC REGIONAL OFFICES Region COVERING THE FOLLOWING COUNTIES: DIVISION OF ENVIRONMENTAL PERMITS (DEP) PERMIT ADMINISTRATORS DIVISION OF WATER (DOW) WATER (SPDES) PROGRAM Onondaga 1 NASSAU AND SUFFOLK 50 CIRCLE ROAD STONY BROOK, NY 11790 TEL. (631) 444-0365 50 CIRCLE ROAD STONY BROOK, NY 11790-3409 TEL. (631) 444-0405 2 BRONX, KINGS, NEW YORK, QUEENS AND RICHMOND 1 HUNTERS POINT PLAZA, 47 -4021ST ST. LONG ISLAND CITY, NY 11101-5407 TEL. (718) 482-4997 1 HUNTERS POINT PLAZA, 47 -4021ST ST. LONG ISLAND CITY, NY 11101-5407 TEL. (718) 482-4933 3 DUTCHESS, ORANGE, PUTNAM, ROCKLAND, SULLIVAN, ULSTER AND WESTCHESTER 21 SOUTH PUTT CORNERS ROAD NEW PALTz, NY 1 2561-1 696 TEL. (845) 256-3059 100 HILLSIDE AVENUE, SUITE 1W WHITE PLAINS, NY 10603 TEL. (914) 428 - 2505 4 ALBANY, COLUMBIA, DELAWARE, GREENE, MONTGOMERY, OTSEGO, RENSSELAER, SCHENECTADY AND SCHOHARIE 1150 NORTH WESTCOTT ROAD SCHENECTADY, NY 12306-2014 TEL. (518) 357-2069 1130 NORTH WESTCOTT ROAD SCHENECTADY, NY 12306-2014 TEL. (518) 357-2045 5 CLINTON, ESSEX, FRANKLIN, FULTON, HAMILTON, SARATOGA, WARREN AND WASHINGTON 1115 STATE ROUTE 86, PO BOX 296 RAY BROOK, NY 12977-0296 TEL. (518) 897-1234 232 GOLF COURSE ROAD WARRENSBURG, NY 12885-1172 TEL. (518) 623-1200 6 HERKIMER, JEFFERSON, LEWIS, ONEIDA AND ST. LAWRENCE STATE OFFICE BUILDING 317 WASHINGTON STREET WATERTOWN, NY 13601-3787 TEL. (315) 785-2245 STATE OFFICE BUILDING 207 GENESEE STREET UTICA, NY 13501-2885 TEL. (315) 793-2554 7 BROOME, CAYUGA, CHENANGO, CORTLAND, MADISON, ONONDAGA, OSWEGO, TIOGA AND TOMPKINS 615 ERIE BLVD. WEST SYRACUSE, NY 13204-2400 TEL. (315) 426-7438 615 ERIE BLVD. WEST SYRACUSE, NY 13204-2400 TEL. (315) 426-7500 8 CHEMUNG, GENESEE, LIVINGSTON, MONROE, ONTARIO, ORLEANS, SCHUYLER,SENECA, STEUBEN, WAYNE AND YATES 6274 EAST AVON -LIMA ROAD AVON, NY 14414-9519 TEL. (585) 226-2466 6274 EAST AVON -LIMA RD. AVON, NY 14414-9519 TEL. (585) 226-2466 9 ALLEGANY, CATTARAUGUS, CHAUTAUQUA, ERIE, NIAGARA AND WYOMING 270 MICHIGAN AVENUE BUFFALO, NY 14203-2999 TEL. (716) 851-7165 270 MICHIGAN AVE. BUFFALO, NY 14203-2999 TEL. (716) 851-7070 APPENDIX E List of 303(d) segments impaired by pollutants related to construction activity, cont'd. COUNTY WATERBODY COUNTY WATERBODY Onondaga Onondaga Creek, Middle and tribs Suffolk Great South Bay, West Onondaga Onondaga Creek, Upp, and minor tribs Suffolk Mill and Seven Ponds Onondaga Harbor Brook, Lower, and tribs Suffolk Moriches Bay, East Onondaga Ninemile Creek, Lower, and tribs Suffolk Moriches Bay, West Onondaga Minor tribs to Onondaga Lake Suffolk Quantuck Bay Onondaga Onondaga Creek, Lower, and tribs Suffolk Shinnecock Bay (and Inlet) Ontario Honeoye Lake Sullivan Bodine, Montgomery Lakes Ontario Hemlock Lake Outlet and minor tribs Sullivan Davies Lake Ontario Great Brook and minor tribs Sullivan Pleasure Lake Orange Monhagen Brook and tribs Sullivan Swan Lake Orange Orange Lake Tompkins Cayuga Lake, Southern End Orleans Lake Ontario Shoreline, Western Tompkins Owasco Inlet, Upper, and tribs Oswego Pleasant Lake Ulster Ashokan Reservoir Oswego Lake Neatahwanta Ulster Esopus Creek, Upper, and minor Putnam Oscawana Lake tribs Putnam Palmer Lake Ulster Esopus Creek, Lower, Main Stem Putnam Lake Carmel Ulster Esopus Creek, Middle, and minor Queens Jamaica Bay, Eastern, and tribs (Queens) tribs Queens Bergen Basin Warren Lake George Queens Shellbank Basin Warren Tribs to L.George, Village of L Rensselaer Nassau Lake George Rensselaer Snyders Lake Warren Huddle/Finkle Brooks and tribs Richmond Grasmere, Arbutus and Wolfes Lakes Warren Indian Brook and tribs Rockland Congers Lake, Swartout Lake Warren Hague Brook and tribs Rockland Rockland Lake Washington Tribs to L.George, East Shr Lk Saratoga Ballston Lake George Saratoga Round Lake Washington Cossayuna Lake Saratoga Dwaas Kill and tribs Washington Wood Cr/Champlain Canal, minor Saratoga Tribs to Lake Lonely tribs Saratoga Lake Lonely Wayne Port Bay Schenectady Collins Lake Wayne Marbletown Creek and tribs Schenectady Duane Lake Westchester Lake Katonah Schenectady Mariaville Lake Westchester Lake Mohegan Schoharie Engleville Pond Westchester Lake Shenorock Schoharie Summit Lake Westchester Reservoir No.1 (Lake Isle) Schuyler Cayuta Lake Westchester Saw Mill River, Middle, and tribs St. Lawrence Fish Creek and minor tribs Westchester Silver Lake St. Lawrence Black Lake Outlet/Black Lake Westchester Teatown Lake Steuben Lake Salubria Westchester Truesdale Lake Steuben Smith Pond Westchester Wallace Pond Suffolk Millers Pond Westchester Peach Lake Suffolk Mattituck (Marratooka) Pond Westchester Mamaroneck River, Lower Suffolk Tidal tribs to West Moriches Bay Westchester Mamaroneck River, Upp, and tribs Suffolk Canaan Lake Westchester Sheldrake River and tribs Suffolk Lake Ronkonkoma Westchester Blind Brook, Lower Suffolk Beaverdam Creek and tribs Westchester Blind Brook, Upper, and tribs Suffolk Big/Little Fresh Ponds Westchester Lake Lincolndale Suffolk Fresh Pond Westchester Lake Meahaugh Suffolk Great South Bay, East Wyoming Java Lake Suffolk Great South Bay, Middle Wyoming Silver Lake Note: The list above identities those waters trom the tinal New York State "2014 Section 303(d) List of Impaired Waters Requiring a TMDL/Other Strategy", dated January 2015, that are impaired by silt, sediment or nutrients. Yl W 1+ 13 C Ln J � cu +� a cu u 0- L C 131 < U 0 C cl�z ,I f I i II II A I� I S 1 Ln E 6 6- Q1 Ln €11 {® Y J Irl #+ vi wl roviro -M O 0 LL ro ro 6el Ul vi Ln E `[] [H Cl4- w -0 _0 LD �0 w pv ; 6-1 ai ca 41 (a 41 ho ii? [ El El■ [1❑ [1 ❑ l IN IN Ln J � cu +� a cu u 0- L C 131 < U 0 C cl�z ,I f I i II II A I� I S 1 Ln J � cu +� a cu u 0- L C 131 < U 0 C cl�z Appendix H Deep Ripping and De -compaction (DEC, 2008) M pct 4 N O o C F3 En O CD `�. CCD En UR c N CD ~ CD C CCD �� �• �� � � O � ¢, � � n � CD 0 • O p CD � p cn cn O a CD CD ~ CD n cr � CD CD "O ° CD CfG c cn CD CD �S CD CD CD C CD° CD CCD cr CO �CD CCD CD p O CCPD O �. °�� °�¢'o a.o 0 0 �. N O n CD CD � � n CD CD o o CD CD CD acn Z� O CD CCD CD ul C O '� � � UG• Q. CDO a d CD � � n CD n ° c CD o c � CD °c O a�o�d cloy �71 CCD UR `G CD CD O n ^� CSD CDcr Q? CD cr CD �71 5 p cr O cr CD O O N N CD CD d �71 v� cn �71 CD CD cr O 0' �J O CD � ~• N CD cr `C n ° v� p? �71 CD cn n O i� En • CfQ CfQ � � CD v� CD (DD U) O 3 NO N ~'• O cn t O d PAL T fw o � NO O EL O CD ° O �-s p CD v, � � � • � CD CD n O p Con Nn CD n CD C� o r • o � �; � ' CD � � s= n CD o CD 't ~7 ~• o N CD C O CD CD ° OCD p O N CDS CD CD n CD N CD CD ^ O � • � CD � CD O O O O � � o d n CD cn Con CD Con CD a �� o o o a o a yCD a � o � p,� ° n° °� ° P 5 `C o o � D ('D �:7" o �. ('D �. o o �, CD o CD -, CD v� CD V� CD �+, o O° O CD a o p o — - O a CD ¢ °•tt�. O No fD �° -° CD CD � or o o 0 00 ,� n CD ° CD CD �71�, o o cD o � o0 �' CDCD s= o oCD p �71 oCDp' o un CD CD zs � �. ° zs ° �, o o �, o o - C _ ,� : o o o zs n ° cD C � Zs P CD C�.. CD un CD 0 a. CDo o °� _ ° ° ,� 7� ° o o o �, -° � � (D�. o O Qn o CD a t CD -� cn o¢ O ocn CL O� + o Qn q � o o �, CD a o o o Qn cncn CD CDCD 0 p CD P7-CD C� p? CD O C7 O N Q. O Z o d CD CD 0 W v� � � " + v, p v, "p �] p N CD �. O 0 pj '� � CD N �• O d d O O Ni O C O �p + CSD CD n a y�71 CD O p (� �71 " " Q. �, . � '"p � . O � O � � �, , F•O `""r � �' �' • CD ^ Y 1 CD � r+' ~ • � ~ . `-s � ~ . `-t � F -t O �, . � � FS' � r -h � . � � CD � � O � � CD �-t (JQ '"i � � v� p p � � O '� �' USG � �-S � CD '•'� USG N � CSD _. ffR O O n v O N N p � �• � � �' � � ,� CSD C ai � � � �' � � N � � N � O � �• � � � � � ~' v, � �• CfG � � � �-h CND �71 O CD n �7, � ~• n — (� CD (71 p � CD v, � CD �h � �, . � ,� CD � � � � v� p? '"O CfG CD n USG ^ CD Con 0 CD n �_ �. O v' O ~• ~. ' Q- CD �1 O nO dR v� O n -O CfQ USG � O O �� p N CSD O ~h n CD `-t CD¢ Q, CD CD CD O (-t 00 rh O� v' n Qn 00 un v'� ~ • CD CD n N ,_`�, n n � y N � • ,�C ,..p n �, . CD ,� ~ • � �' � CD � � C F� ~ . � � CD C � `""v � O � `""r � � � � v� O CD O v' �' • � CD Ftp � � '� 'i� � Q-: CD CD � � ~ . C � CD O CD O �C FO F� CD O � � O v,p cr CD �t OCD �:T � USG n�71 �+ (req O ,:T 45 p n ('D CD �' � n n n O CD FO �7 CD � n v �, �• n n n " Con00 ' Q �� N O CDcn cn"d NCD "1 �_ ��t � � '�,�' • � �N�!! CD C� CD (71 v� -tt CfG N O `�� p CD IJj l I Y'CD /C FCD /� CD U] \ V CD Fri y� O J `•f O CD O O - Un CD US PDV i -- cni O cn 0 CD CDF� • F� �� l V F� /y^ V fY -t -- p r� r� �� ~� r� p p v� p p �' C� N `~ . p CD aq ul O Fri CD F� • FCBD ice+ V F� � F� � � �� /T �� O l V /�� ((�(�� p cn p �-t UG Z; CfG ~ - UG Q. O Z o F� . �] �� � v, CD O C C y�71 CN cn �71 cr . Fp crcr N 00 (� CJS >~ � n C Q. O Z o F� . �] �� � v, Q, `C cn O C C C y�71 CN cn �71 cr . Fp crcr N 00 CD C'n CD un CD CD CD �-h CND �71 O CD n �7, � p N n O � v, n '� � ffQ O O v, � CD F•O '-p N i N C O CD �1 CD CD ..� Qn n n ¢ crcr CCD n O v' v,p cr O �t O �:T � USG n�71 �+ (req O ,:T 45 p n ('D CD �' � n n n O CD FO n � Qn �. n cn y N CC D CD NCD "1 �_ ��t � � '�,�' • � �N�!! CD C� CD (gyp Con O . P O CDCD P, N �. p qQ �' ° n0 (G ° CD �. FD CSD P � � O CD r+ NN CD CfQ C N �71 CD ° CDCD ,� O ° CSD O O. (71 O (7, CD CD EL CD P ° N ►fit . CD 0 CD CD aq O (rQ n CD CD 'O p C -D 00 Or �, p' O O (DD CSD N `C p �,' N G n ►� VCD cFq uQ CD CCD W "O O O CD qQD ¢ n r+ N t P7�� ~ ttGQ n N n O �. N O n � � O '� p O �. O� � � � -O GQ n N O O O O O N CPQ �• � � � � � � ° p' o`er � � � � � � � '� � qQ CD 0 CD r) n'� cam. w O'Q 00 `�C N qQ ° O qQ ¢, CPQ CD CD O CD Q-. CD CD "O CD CD Q-. � + CSD 0 n n CD CD N d� CDn v� (-D `r N CD n CD n CD � �• � O "i CD � O`C�q'�• n n -� 0 CD O O r O O CD CD n C -D CDo d CD `r CD � � � • CfQ CD ('D O O �t- �b �- 6 C''O�D CCD O � � 00 CDn CD � O � o � _ CD - N �7TJ C -D nCD IC D n � O C -D CD CfQ W 00 P CD COD CJQ D CD CD p CL n CD y Q �� CD ° CD n o qQ .b CD :. I C -D CD CD V `� CSD CD CD CD �p O CSD N CD O O CD n � O O0 CD �. NO CD v' O C1Q Q- O • N v� H r+ �-h tt Q- r CD CD CD ~- CD -- -s v� CSD CD�a ���0 CD CD � � CD O � �.CDCD n N O~ N O~ P CD O CD � �-h CSD CD OCD CSD � P CD O n v,' • ! �' CD CD C ° n CD . CD r) CD � CDCD v� ^ CDN On CD O n v� (71 s= 0 n n p CD CD CD CD ° O � CD p O O CD �j �. O C -D~ CD CD O CD CD n N O ~-' C�.;D O CD CSD CSD n CCD O O O' CD CD O OCD CD CCD -O ¢ O CDCD o �o CD CD � CD .� O n UQ P O UQ n n CD O ¢, CD �71 n CfQ � p N CD O CD CD CCD O N O O CD C -D o � Q � �-t� o C �. O C `� �-t �• N � O � ° b a O n CSCDD N �• p c CD N C N n C-4 �r `� CD qQ 110 P CD N O �.(f�R -O N CIQ C-+ CPQ �1 CCD CfQ con o 0 �- �- -O n Up 0 o cn �-s CD O CSD �7 C cn O cn CAN �7r+ �7 CD O CD an O O (71 O N¢ CfQ an O -t '"O CD O cn Q.- It O O �� -'•�+ �71 y n y CD FS �7 x s O � ¢ I.; � r O � O O � H� I ul Un � • O1"r I --e • �_• Vhfe+ del '_ cn ' *. - _ P �71 y n y CD FS �7 � CD � ''Q O � � � • V v � rr � $= O � H� F-, NCD v� C �71 • C7 C O �' � �-' • CD CfG v�CDnp,PD n � n0 n O v� n CD CD � • �q O � � CD `C b9 O CD O v� O 01 x O CDO Qn C CD an an O.• O O O, ,:� CD CDQ- CDCD CD CD O (� � 0 � -� CD CD N CCD O n0 CD O (� cr Qr CD CD p) n n C Qr C CD r+ O O CD O CD O �71 CD N -O or n CUD'CD w p p o o C -D o CD O � • CD N CD O n CD CD CfG n bg CfQ CD CD 0 CD � CCD v, O n � o 110cry CD 7� CD o •-s O n s �, ► s CD � CD CD P CD CD 0 Qn CD �. CD �. n t � CD O NUS � O CD O n (TG CD CCD CD 0 CD Qn CSD Q, CCD W 00 r �' CSD CD 'O CD CD CDCD �. CD CDC CSD ¢ C nor � O crc' n' n CD CD CD o nn p, - b y CDCD O �_ V' CD CSD N Qn CSD CD CD , + � � CD � k� n- � � ''d n � �,• � C � � C � � � O X Cn rl � r n. o' rr) aq CrJ d z A cin FT 00 °0 CD rl (OL D `- fi [DCL _ n m c n n �. n7 ar oCD r rl~' cG Cil o � � C � � � o �. � M 0 is aCi � n m W� Ocl.� r n w Izin QP(D ~ O O �.. Qn O CD ��• -Itun o a n' O o co' p n y Z co m C1) un Q3 n p' `. �.• i p fD N CID `C rrr W O Un rl p cn - co CD n a A� Z OI �_ c p r