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HomeMy WebLinkAbout20221088 177 S Broadway & 28 Lincoln Stewarts SWPPP STORMWATER POLLUTION PREVENTION PLAN Prepared for Proposed Convenience Store & Gas Station 177 South Broadway City of Saratoga Springs, Saratoga County, NY 12/28/2022 Prepared by: Scott E. Kitchner, PE Stewart’s Shops PO Box 435 Saratoga Springs, NY 12866 Phone: (518) 581-1201 Ext. 4249 Fax: (518) 581-1209 skitchner@stewartsshops.com TABLE OF CONTENTS I INTRODUCTION II BACKGROUND INFORMATION III CONSTRUCTION DRAWINGS IV SOIL DESCRIPTION V CONSTRUCTION PHASING VI POLLUTION PREVENTION MEASURES VII SOIL STABILIZATION MEASURES VIII EROSION AND SEDIMENT CONTROL PRACTICES IX MAINTENANCE SCHEDULE AND SWPPP IMPLEMENTATION X RECEIVING WATERS XI STORMWATER RUN-OFF CHARACTERISTICS XII CONSTRUCTION ACTIVITIES MEETING CONDITIONS IN TABLE 2 OF APPENDIX B XIII SWPPP DEVELOPMENT – 6 STEP PROCESS XIV FLOOD HAZARD XV WETLANDS XVI HISTORIC AND CULTURAL RESOURCES XVII ENDANGERED SPECIES XVIII MATERIALS AND SUBSTANCE MANAGEMENT XIX BEST MANAGEMENT PRACTICES XX SPILL PREVENTION PRACTICES APPENDICES A. CONSTRUCTION / OPERATION AND MAINTENANCE / INSPECTION REPORT FORMS, INSPECTOR CERTIFICATION FORM, INSPECTION LOG, CORRECTIVE ACTION LOG, SWPPP INSPECTION REPORT FORM. B. CONTRACTOR CERTIFICATION FORM, CONSTRUCTION ACTIVITY FORM C. STORMWATER MANAGEMENT REPORT D. NYSDEC ENVIRONMENTAL MAP, FEMA MAP & NYS OFFICE OF PARKS, RECREATION AND HISTORIC PRESERVATION (OPRHP) CORRESPONDENCE E. CONSTRUCTION DRAWINGS F. SWPPP REVISIONS/UPDATES I. Introduction Stewart’s Shops is proposing to redevelop two parcels located in the City of Saratoga Springs, NY, to construct a new 3,720 sq. ft., 2 story building and replace the existing 1,795 sq. ft. canopy in kind. The project site is located at 177 South Broadway. This report will address the required components for a Stormwater Pollution Prevention Plan (SWPPP) as specified by the New York State Department of Environmental Conservation SPDES General Permit for Stormwater Discharges from Construction Activity Permit No. GP-0-20-001. II. Background Information A. Existing Conditions: The project includes two (2) parcels to create a 0.58+/- acre project area. The combined properties consist of a 1,923+/- sq. ft. Stewart’s Express commercial building, a 1,795+/- sq. ft. fuel canopy, and a 1,554+/- sq. ft. residential home and associated paved parking and delivery areas with one access drive on Lincoln Ave. and one access driveway on South Broadway (US Rte. 9). The site is bordered to the North by Lincoln Ave., East by South Broadway (US Rte. 9), to the South by commercial property, and to the West by a residential property. B. Proposed Conditions: The scope of the project includes the demolition of the residential home, Stewart’s Express and associated access drives, and parking areas to incorporate the construction of a new 3,720 sq. ft. Stewart’s Shop and underground fuel storage. The new shop will utilize the existing 1,795 sq. ft. canopy with (4) fuel islands. Proposed features will include new landscaping, lighting, paved parking, access drives, utility and storm water management improvements as shown on the Site Plan drawings prepared by Stewart’s Shops. Per the requirements set forth in the NYSDEC Stormwater Design Manual, this project classifies as a redevelopment activity with an increase in impervious cover. Per Chapter 9 of the NYSDEC Stormwater Design Manual, Section 9.2.1 I, the Water Quality Volume WQv objective for a re-development activity can be achieved by proposing treatment of 25% of the existing impervious cover in a standard practice and 100% of the new impervious in a standard practice. Per the Unified Development Ordinance (UDO) of Saratoga Springs, Article 17, “Post- construction requirements are limited to 100% of the Runoff Reduction volume (RRv) from new impervious cover and 50% of the RRv from existing/redeveloped imperious cover using accepted RRv criteria and methods as prescribed by the New York State Stormwater Management Design Manual.” The proposed stormwater management system exceeds these requirements as discussed in greater detail in the Stormwater Management Report included in this SWPPP. Stewarts Shops will be responsible for all construction activities, post construction operations and maintenance of the system and all responsibilities specified in the SWPPP. III. Construction Drawings: Included in this report are the following drawings: • Existing Site Plan – Existing condition for the parcel including all required existing information (watercourses, topography, vegetation, utilities, property boundaries, etc.) • Proposed Site Plan – Comprehensive plan of all proposed improvements and limits of disturbance. • Utility Plan – Plan includes detailed design information for the installation of all proposed utilities resulting in the disturbance of soil for this project. • Grading – Plan illustrates existing and proposed slopes and proposed spot grades, • Stormwater Management Plan – proposed stormwater quantity and quality mitigation measures. • Erosion and Sediment Control Plan – Erosion and sediment control measures to be in place and inspected, prior to commencement of construction. The proposed measures were designed in accordance with the New York Guidelines for Urban Erosion and Sediment Control. Proposed measures include inlet protection, concrete washout, silt sock/fence along the project perimeter, stabilized construction entrance and construction sequencing. • Landscaping Plan – Included is all proposed landscaping for the project. • Photometric Plan – Includes proposed lighting and foot candle measurements. • Vehicle Tracking Plan – Includes a path of travel for the largest vehicle that will utilize the site. • Stormwater Details – Includes all details associated with the Stormwater Management Plan. • Miscellaneous Details – Includes all details for utilities and misc. features. IV. Soil Description: Data supplied by the USDA Natural Resources Conservation Service (NRCS) indicates that site soils are primarily classified as Windsor loamy sand. The soils are further classified as being Hydraulic Soils Group A and excessively drained. NRCS soil data can be found in the Stormwater Management Report included in the appendices. The soil composition and groundwater have been verified from a previous soil boring report. Due to weather and site restrictions, test pits and infiltration have not been performed to date. The conductivity of the soil has been limited to a conservative 15 in/hr for this design. The actual soil infiltration rates will be tested when weather permits, at which time the design will be modified, if necessary, to align with the findings. V. Construction Phasing: Construction sequencing, limits of clearing and grading, utility and infrastructure installation and all other associated activities resulting in soil disturbance are detailed on the Erosion and Sediment Control, Grading, Stormwater Management, and Utility Plans. The following construction sequence is recommended: Fall • Install silt sock/fence around house. • Clear required area between existing store and 2 story house. • Demolish residential house and backfill. • Stabilize disturbed areas for winter construction hold. Spring • Install construction entrance. • Install silt sock. • Demo existing shop and canopy. • Remove all existing asphalt and concrete. • Remove existing structures and utilities. • Rough grade new building site area. • Install new stormwater structures. • Install U.G. fuel tanks and conc. apron. • Install building utilities, foundation, construct building. • Construct fuel canopy. • Install stormwater infiltration system. • Install subbase for parking lot. • Finish grade around building. • Rough grade proposed gas island area. • Install remaining subbase and pave. • Complete soil restoration. • Finish grade area and seed greenspace areas. • Install landscaping, mulch, etc. • Remove temporary erosion control measures as order by qualified inspector. VI. Pollution Prevention Measures: Pollution Prevention measures during construction are detailed on the SWPPP / Erosion and Sediment Control Plan. Construction waste will be disposed in on-site construction dumpsters immediately. Any materials or chemicals considered to be hazardous shall be covered or stored in construction trailers to ensure no discharge to stormwater will occur. VII. Soil Stabilization Measures: Initial clearing and grading will commence once the proposed erosion and sediment control practices are in place as detailed on the erosion and sediment control plan and approved by both the SWPPP Monitoring Professional. Erosion and sediment control practices to be installed during earthwork activities include a stabilized construction entrance, silt sock/fence, concrete washout area, inlet protection, silt sock/fence around base of any stockpile areas. Mulch will be placed within landscaped areas as noted on the Landscaping Plan. Seeding will be placed on site where specified on the Landscaping Plan to establish a permanent vegetative cover. Topsoiling will be utilized in areas where soil disturbance occurs by placing 6 inches of topsoil to aid in establishing permanent vegetation cover. The permanent structural erosion and sediment control practice that will be utilized is land grading and establishment of turf. Land grading will occur in areas specified on the Grading Plan to ensure proper drainage and proper elevations for the proposed building and stormwater facilities. VIII. Erosion and Sediment Control Practices: Specific types, sizes, lengths, and dimensions for all erosion control practices and sizing for temporary sediment basins are detailed on the Erosion and Sediment Control Plan and Detail Sheet. All temporary erosion control practices shall be in place prior to construction and shall remain until the limits of disturbed areas are stabilized. Dust control will be implemented to prevent surface and air movement of dust from disturbed areas. Silt sock/fence will be installed on the downslope of disturbed to intercept sediment runoff from small drainage areas of disturbed soils. A stabilized construction entrance will be provided with aggregate with geotextile where traffic will be entering/exiting the site. IX. Maintenance Schedule and SWPPP Implementation: Maintenance of the proposed erosion and sediment control practices are detailed on the Erosion and Sediment Control Plan. Included in this report are Construction Inspection and Operations and Maintenance Checklists. The operator is ultimately responsible for inspection and maintenance during construction. Stabilization must be achieved prior to removal of temporary erosion and sediment control devices. The SWPPP Monitoring Professional must inspect and approve final stabilization prior to the removal of these devices. Stewarts Shops as the operator, shall have each contractor and sub-contractors identify at least one (1) person responsible for SWPPP Implementation. This person must be trained and certified by the NYSDEC as stated on Page 12, Part III.A.6 of the NYSDEC General Permit GP-0-20-001 included in the appendix of this report. Stewarts Shops, as the operator, shall designate an inspector meeting the qualifications as set forth on page 18, Part IV of the General Permit. The inspector shall be responsible for the construction phase of the project and the implementation of the pollution prevention measures set forth in this report. The designated individual shall have a complete understanding of all components of the stormwater management system. Delineation of SWPPP implementation responsibilities for the construction phase of the project are detailed in the Erosion and Sediment Control Plan. The plan details structural practices proposed to divert flows from exposed soils, store flows, and limit run-off and discharge of pollutants from exposed areas of the site during construction. Stewarts Shops shall also designate a qualified representative for the post development inspection and monitoring. The inspector shall follow the guidelines of the Operations and Maintenance Checklists included in this report. The inspector shall keep a continuous record of all inspection checklists, maintenance and repairs and shall make them available to the City at their request. 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 New York State Department of Environmental Conservation SPDES General Permit for Stormwater Discharges Permit number GP-0-20- 001. The owner or operator of each construction activity 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. 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 New York State Department of Environmental Conservation SPDES General Permit for Stormwater Discharges Permit number GP-0-20-001 as soon as soil disturbance activities resume. For construction sites where soil disturbance activities have been shut down with partial project completion, the trained contractor may 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. The owner or operator shall have a qualified inspector conduct site inspections in conformance with the following requirements: 1. A qualified inspector shall conduct site inspections for all construction activities identified in Tables 1 and 2 of Appendix B of New York State Department of Environmental Conservation SPDES General Permit for Stormwater Discharges Permit number GP-0-20-001. 2. Unless otherwise notified by the City, the qualified inspector shall conduct site inspections in accordance with the following timetable: 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 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 City of Saratoga Springs Stormwater Management Office 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 City of Saratoga Springs Stormwater Management Office 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. 3. At a minimum, the qualified inspector shall 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; i. 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 l. 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 New York State Department of Environmental Conservation SPDES General Permit for Stormwater Discharges Permit number GP-0-20-001 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 New York State Department of Environmental Conservation SPDES General Permit for Stormwater Discharges Permit number GP-0-20-001, the inspection reports shall be maintained on site with the SWPPP. X. Receiving Waters: The proposed stormwater management system is designed to capture and treat 100% of the required WQv via infiltration with NYSDEC approved redundant pre-treatments for all anticipated storm events. XI. Stormwater Run-off Characteristics: Existing and proposed data describing stormwater run-off characteristics are included in the Stormwater Management Report, prepared by Stewarts Shops. This report is included in the Appendix. XII. Construction Activities Meeting Conditions in Table 2 of Appendix B This project includes construction activities that involve soil disturbances of less than one (1) acre and is not subject to NYSDEC SWPPP requirements. However, disturbance falls within the 0.50-0.99 acres of land and meets the criteria in Article 17 of the Saratoga Springs UDO requiring a full SWPPP. Therefore, the following information is provided: 1. Descriptions of each post-construction stormwater control practice are included in the Stormwater Management Report and are detailed on the Grading and Drainage Plan included in the Appendix of this report. 2. Hydrologic and hydraulic analyses for all structural components of the stormwater control system, for all applicable design storms, are included in the Stormwater Management Report. 3. Comparison of pre and post development stormwater run-off conditions is included in the Stormwater Management Report. 4. Dimensions, materials, and installation details for all post construction strormwater control practices are specified on the enclosed Grading and Drainage Plan. 5. A maintenance schedule is detailed on the Erosion and Sediment Control Plan and in the Operations and Maintenance Checklists included in this report. XIII. SWPPP Development – 6 Step Process: 1. Site Planning - Green Infrastructure 2. WQv Determination 3. Apply GI Practices and Standard SMP’s with RRv Capacity 4. Determine minimum RRv 5. Apply Standard SMP’s to address remaining WQv, if required 6. Apply volume and peak control 1. Site Planning – Green Infrastructure: A. Preservation of Natural Resources: 1. Preservation of Undisturbed Areas Construction and/or silt sock/fence shall be installed along the perimeter of the limits of disturbance of the site. The operator and contractors shall be instructed not to disturb any soil or vegetation beyond the limits of construction as noted on the plans. The size of the site and undisturbed area does not justify the delineation of permanent conservation easements. 2. Preservation of Buffers Existing vegetative and wooded buffers beyond the limits of the proposed redevelopment will be maintained as shown on the Site Development Plan for the project. 3. Reduction of Clearing and Grading The limits of clearing and grading have been proposed at a minimum needed to construct the proposed facility. 4. Locating Development in Less Sensitive Areas The proposed development will not result in adverse impact to sensitive resource areas such as floodplains, steep slopes, erodible soils, wetlands, mature forests and critical habitats. 5. Open Space Design The proposed layout of this facility has been designed as conservatively as practical to reduce impervious coverage, preserve open space and protect water resources, while maintaining adequate space for access, parking and building area needed for the proposed use. 6. Soil Restoration / Preservation Per Section 5.1.6 of the NYSDEC SEDM, soil restoration techniques shall be applied to this project. The specifications listed in this section, particularly in areas of cuts/fills and existing impervious areas that will be converted to pervious areas, shall be performed across the project site. As the project is considered a Redevelopment Activity, Soil Restoration is required in areas where existing impervious areas will be converted to pervious surfaces. The following techniques shall be applied: • Following removal of the impervious cover, three (3) inches of compost shall be applied over the subsoil surface. Compost shall be aged, from plant derived materials, free of viable weed seeds, have no visible free water or dust produced when handling, pass through a ½” screen and have a suitable pH for plant growth. • Compost shall be tilled into the subsoil to a depth of at least twelve (12) inches using a cat-mounted ripper, tractor-mounted disk or tiller. • Any uplifted stone/rock material of four (4) inches or larger in size shall be removed. • Six (6) inches of topsoil shall be applied and the areas shall be vegetated in accordance with the approved Plan. B. Reduction of Impervious Cover 1. Roadway Reduction Roadway reduction is not applicable to this project. 2. Sidewalk Reduction The sidewalks have been designed at a minimum width and length to provide safe access through and around the site. 3. Driveway Reduction The access drives have been designed at a minimum width and length to provide safe access through the site. 4. Cul-de-sac Reduction Cul-de-sac reduction is not applicable to this project. 5. Building Footprint Reduction The building footprint has been designed at a minimum footprint to meet the needs of the intended use. 6. Parking Reduction The parking areas have been designed to provide the minimum number of spaces needed for the intended uses. 2. Determining Water Quality Volume: The Water Quality Volume (WQv) has been calculated per the NYSDEC SWDM and is shown in the details section of the Storm Water Management Report. 3. Runoff Reduction:  The Runoff Reduction Volume (RRv) has been limited to 100% of the required WQv  for the proposed areas of development.    4. Minimum RRv:  The Minimum Runoff Reduction Volume does not apply as The City of Saratoga  Springs has a more restrictive regulation.   5. Apply SMP’s to Address remaining WQv:  The Water Quality Volume (WQv) treatment objective has been achieved by  infiltration and NYSDEC approved pre‐treatment via a First Defense Hydrodynamic  Treatment System and an oil/water separator.  6. Apply volume and peak rate control practices:  The proposed infiltration system results in a reduction in off‐site peak flow rates for  the 1, 10, and 100 year storm events.  XIV. Flood Hazard:  The Flood Hazard Boundary Maps for the project area (36091C0433E) dated August 16,  1995 were reviewed (See Appendix D).  The Federal Emergency Management Agency  (FEMA) mapping indicates that the proposed project is located in Zone X which is  determined to ne outside the 0.2% annual chance floodplain.    XV. Wetlands:  The project area was reviewed utilizing the online Environmental Resources Mapper  provided by the NYSDEC (See Appendix D).  Based on the information provided by the  NYSDEC Mapper, there are no state or federally regulated wetlands that will be  impacted by the proposed project.  XVI. Historic and Cultural Resources:  The project area was reviewed by the NYS Office of Parks, Recreation and Historic  Preservation (OPRHP) and they have determined that no properties, including  archaeological and/or historic resources, listed in or eligible for the New York State and  National Registers of Historic Places will be impacted by this project. (See Appendix D).       XVII. Endangered Species: The NYSDEC Environmental Resource Online Mapper was reviewed, and it was determined two (2) species of butterfly, the Frosted Elfin and Karner Blue, are listed to be in the vicinity of the project site. However, the site is fully developed and there is no existing habitat for these species. XVIII. Materials and Substance Management: The materials and substances listed below are expected to be on site during construction. 1. If construction vehicles are to be re-fueled on site, petroleum products will be stored in above ground storage tanks. The tanks will either be steel with an enclosure capable of holding 110% of the storage tank volume or Convault-type, concrete encased type with integral secondary storage. Hydraulic oil and other oils will be stored in their original containers. Concrete and asphalt will be stored in the original delivery trucks. 2. 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. 3. Paints or other similar materials will be stored in their original containers and all empty containers will be disposed of in accordance with label directions. 4. Portable sanitary facilities, which contain chemical disinfectants (deodorants), will be located on site, with the disinfectants held in the tank of the toilet. All waste materials generated during construction will be disposed of in a suitable landfill, transfer station or Construction & Demolition landfill. Any hazardous waste generated during demolition or construction operations will be disposed of by a licensed hazardous waste carrier at a suitable disposal facility. If unexpected hazardous waste is discovered during construction, the related work in that area will cease until the issue is resolved. Portable temporary sanitary facilities will be serviced regularly. XIX. Best Management Practices: During construction, the following procedures and practices will be followed on site to reduce the risk of spill or other accidental exposure of materials and substances to stormwater runoff: 1. Equipment cleaning, maintenance and repair will be conducted in designated areas protected by berms. 2. Sediment and erosion controls will be inspected weekly for sediment build-up and failure. The controls will be cleaned at the discretion of the Qualified Inspector. 3. Cleared brush, debris and soils will be stockpiled up slope from and protected by erosion and sediment controls. 4. Materials brought on site shall be in the minimum quantities required. 5. All materials stored on site will be stored in a neat, orderly manner in their appropriate containers, and if possible, under a roof or other enclosure. 6. Products will be kept in original containers with the original manufacturer’s labels and safety data sheets will be retained. 7. Substances will not be mixed with one another unless recommended by the manufacturer. 8. Whenever possible, the entire product will be used up before container disposal. Recycle empty containers as applicable. 9. Manufacturer recommendations for proper use and disposal will be followed. 10. All above grade storage tanks are to be protected from vehicle damage by temporary barriers. XX. Spill Prevention Practices: The following practices will be followed for spill prevention and cleanup. The site contractor responsible for the day-to-day site operations will be the spill prevention and cleanup coordinator. He/she will designate at least one 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 on-site construction office or trailer. 1. Manufacturer’s 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 (2) gallons will be reported to the NYSDEC Regional Response Unit. Notification to the NYSDEC (1-800-457-7362) must be completed within two hours of the discovery of the spill. This is a legal requirement that must be complied with. 2. Materials and equipment necessary for spill cleanup will be kept in the material storage area on site. Equipment and materials will include, by 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. 3. All spills will be cleaned up immediately after discovery. 4. The spill area will be kept well ventilated, and personnel will wear appropriate protective clothing to prevent injury from contact with spilled substances. 5. Spills of toxic or hazardous materials will be reported to the appropriate State of local government agency, regardless of size. 6. Concrete trucks will not be allowed to wash out or discharge surplus concrete or drum water on site, except in areas specified. 7. Asphalt trucks shall not discharge surplus asphalt on site, except in areas specified. A. CONSTRUCTION / OPERATION AND MAINTENANCE / INSPECTION REPORT FORMS, INSPECTOR CERTIFICATION FORM, INSPECTION LOG, CORRECTIVE ACTION LOG SWPPP INSPECTION REPORT FORM Operation and Maintenance Manual First Defense® and First Defense®High Capacity Vortex Separator for Stormwater Treatment INSPECTION CERTIFICATION FORM Name New York SPDES Permit number (fill in when obtained) Certification: “I 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 there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations.” Signature Date Title SPDES GENERAL PERMIT GP-0-20-001 SWPPP CONSTRUCTION INSPECTION LOG DATE/TIME REASON WEATHER SOIL ASSESSMENT CONDITIONS DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I DATE: TIME: NAMEITITLE/SIGNATURE OF INSPECTOR: I CORRECTIVE ACTION LOG Date: Description: Corrective Action: Stewart’s Shops, Corp. Routine Weekly Inspection Stormwater Pollution Prevention Plan Construction Inspection Form Page 1 of 2 Site Assessment / Inspection Report SWPPP Construction Activities Stewart’s Shops Corp. 177 South Broadway City of Saratoga Springs, Saratoga County, New York General Permit: GP-0-20-001 Permit ID: NYR Weather:__________________________________ Temperature:_______________________________ Date:_____________________________________ Time:____________________________ a.m. p.m. Soil Condition:_____________________________ Contractor:_________________________________ Observation Instructions: On a site map, indicate the extent of all disturbed areas and drainage pathways. Indicate site areas are expected to undergo initial disturbance or significant site work within the next 14-day period. Indicate on a site map all areas of the site that have undergone temporary or permanent stabilization. Indicate on a site map all areas that have not undergone active work during the previous 14-day period. Inspect all sediment control practices and record the approximate degree of sediment accumulation as a percentage of the sediment storage volume. Note if a substantial increase in turbidity in downstream water courses/bodies exist. Inspect all erosion and sediment control practices and record all maintenance requirements such as verifying the integrity of sediment control barriers or diversion systems (i.e. silt fence, diversion swales, earthen berms, etc.) and containment systems (i.e. sediment basins and sediment traps, etc.). Inspect all equipment, material handling or storage areas for evidence of apparent spills, leaks or deleterious materials. Stewart’s Shops, Corp. Routine Weekly Inspection Stormwater Pollution Prevention Plan Construction Inspection Form Page 2 of 2 Practice Condition Comments Stabilized Construction Entrance Good / Fair / Poor / N/A Temporary Parking Good / Fair / Poor / N/A Silt Fence Good / Fair / Poor / N/A Temporary Swales & Berms Good / Fair / Poor / N/A Check Dams (Stone) Good / Fair / Poor / N/A Slope Protection Good / Fair / Poor / N/A Dewatering Operations Good / Fair / Poor / N/A Sediment Traps Good / Fair / Poor / N/A Inlet Protection Good / Fair / Poor / N/A Mulching I Seeding Good / Fair / Poor / N/A Temporary Stockpiles Good / Fair / Poor / N/A Dust Control Good / Fair / Poor / N/A Sedimentation on Public Streets Good / Fair / Poor / N/A Less Than 5 Acres of Disturbance Good / Fair / Poor / N/A Other: Good / Fair / Poor / N/A Other: Good / Fair / Poor / N/A Non-conforming work item still outstanding (list item number): Inspection Notes: Inspectors Signature: ______________________________________________Date:_________________ Inspectors Printed Name: __________________________________________ U.S. ROUTE 9 BROADWAY LINCOLN AVENUE U.S. ROUTE 9 BROADWAY LINCOLN AVENUE B. CONTRACTOR CERTIFICATION FORM CONSTRUCTION ACTIVITY FORM CONTRACTOR CERTIFICATION FORM Proposed Convenience Store & Gas Station 177 South Broadway City of Saratoga Springs, NY Saratoga, NY Contractor responsible for the implementation of the SWPPP: Company Name Business Telephone Number Business Address City, State, Zip Code Business Facsimile E-mail Address CERTIFICATION: "I hereby certify 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 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 proceedings." Signature Date Printed Name Title Company Name Business Telephone Number Business Address City, State, Zip Code CONSTRUCTION ACTIVITY FORM NOTE: The contractor is responsible for maintaining an accurate and complete log of construction activities, including, but not limited to, commencement of stabilization, major grading activities, timeframes when construction ceases on a portion of site (temporary or permanent) until the Notice of Termination (NOT) is filed. MAJOR STABILIZATION AND GRADING ACTIVITIES Construction Activity Contractor Name Start Date End Date Location C. STORMWATER MANAGEMENT REPORT STORMWATER MANAGEMENT REPORT Prepared for Proposed Convenience Store & Gas Station 177 South Broadway City of Saratoga Springs, Saratoga County, NY 12/28/2022 Prepared by: Scott E. Kitchner, PE Stewart’s Shops PO Box 435 Saratoga Springs, NY 12866 Phone: (518) 581-1201 Ext. 4249 Fax: (518) 581-1209 skitchner@stewartsshops.com TABLE OF CONTENTS SECTION I. INTRODUCTION II. EXISTING STORMWATER CONDITIONS a. EXISTING STORMWATER CONDITIONS SUMMARY b. EXISTING WATERSHED PLAN III. PROPOSED STORMWATER CONDITIONS a. PROPOSED STORMWATER CONDITIONS SUMMARY b. PROPOSED WATERSHED PLAN c. IMPERVIOUS COVER COMPARISON PLAN d. CONCLUSION e. PRE AND POST DEVELOPMENT FLOW RATE COMPARISON TABLE f. WATER QUALITY VOLUME (WQv) AND PEAK DISCHARGE FLOW (QP) CALCULATIONS g. PRE AND POST DEVELOPMENT WATERSHED CALCULATIONS AND HYDROGRAPHS FOR THE 1, 10, AND 100 YEAR STORM EVENTS h. NRCS SOILS DATA i. NRCC EXTREME PRECIPITATION TABLES I. Introduction Stewart’s Shops is proposing to redevelop two parcels located in the City of Saratoga Springs, NY, to construct a new 3,720 sq. ft., 2 story building and replace the existing 1,795 sq. ft. canopy in kind. The proposed features include landscaping, lighting, decorative brick landscape wall, paved parking and access drives, perimeter sidewalks, trash enclosure, utilities and stormwater management improvements as shown on the Site Plan drawings prepared by Stewart’s Shops. The site is located at 177 South Broadway and includes the parcel at 28 Lincoln Ave. to form a .58 +/- acre project area. The parcels will remain separate as the 177 S. Broadway parcel is a long-term land lease to Stewart’s Shops and 28 Lincoln Ave. is under contract to purchase by Stewart’s Shops. This report will briefly discuss the proposed site development and provide a detailed analysis of the existing and proposed site conditions and the proposed stormwater management system. Hydraulic calculations included in this report were generated for the 1, 10, and 100-year storm event utilizing the SCS TR-20 and HydroCad Stormwater modeling software. Rainfall quantities were obtained from Cornell University at precip@cornell.edu who have compiled data in collaboration with the Northeast Regional Climate Center (NRCC) and the USDA National Resources Conservation Service (NRCS). II. Existing Stormwater Conditions Existing Conditions Summary: The project area currently consists of one (1) 1,554 sq. ft. multifamily home at 28 Lincoln with a full foundation; and one (1) 1,923 sq. ft. Stewart’s Express convenient store constructed as slab on grade, and one (1) 1,795 sq. ft. fuel canopy at 177 S. Broadway. The combined parcels have two (2) access drives on Lincoln Ave. and one (1) access drive on South Broadway. There are three (3) primary existing watersheds on the site which have been designated Watershed DA1, DA2, and DA3 in this report. DA2 has been further broken down into two (2) separate subcatchments, DA2a & DA2b, to analyze the impact the existing drywell has on discharge point #2 (DP2). Watershed DA1 includes the 57% of the development area. Stormwater from this area is collected on site in a series of drainage structures and piped to a city drainage structure on South Broadway. This drainage structure is referred to as discharge point #1 (DP1) in this report. Stormwater from the site and surrounding roads flows primarily in a southeasterly direction via sheet flow, drainage structures, pipes, and tributaries ultimately discharging to Saratoga Lake. Watershed DA2 is 4,883 sq. ft. and includes two (2) smaller subcatchments, DA2a and DA2b. DA2a is 2,227 sq. ft. area of mostly asphalt located within the parcel that flows to a drywell at the northwest quadrant of the site. When this drywell is surcharged, it will outlet through the grate and flow to Lincoln Ave. DA2b is 2,656 sq. ft. of mostly impervious surfaces within the ROW that sheet flows to Lincoln Ave. Collectively, these areas discharge to the Lincoln Ave. ROW and flow in a westerly direction to a city drainage structure and into the city storm sewer where it ultimately discharges to tributaries of Saratoga Lake. Watershed DA3 is 7,234 sq. ft. that sheet flows over grass to the southwest to neighboring properties. Any water not infiltrated will end up at Hamilton Street where it is collected by a city drainage structure and into the city storm sewer where it ultimately discharges to tributaries of Saratoga Lake. The existing watershed area and topography are illustrated on the Existing Watershed Plan included on the following pages of this report. Project #Sheet # 1 of 1 Page # 1 of 1 Created By:Date: Checked By:Date: Project:Revised By:Date: Subject:Checked By:Date: %CN 1,978 Lawn Area, Good 12% 4.8 14,225 Paved Parking, Roof, etc.88% 86.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 16,203 100% %CN 1,187 Lawn Area, Good 24% 9.5 3,696 Paved Parking, Roof, etc.76% 74.2 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 4,883 100% %CN 4,798 Lawn Area, Good 66% 25.9 2,406 Paved Parking, Roof, etc.33% 32.6 30 Gravel 0% 0.3 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 7,234 100% = 0.166 acres sq. miles 0.000 Area Land Use Area (feet2) Land Use / Cover Description Hydrologic Soil Group Actual CN Area (feet2) Factored CN Weighted CN #3 A397,234 59 A98sq. feet A76 = sq. miles = 0.112 0.000 Area (feet2) Factored CN Weighted CN #2a + #2b A394,883 84 A98sq. feet = Area Land Use Area (feet2) Land Use / Cover Description Hydrologic Soil Group Actual CN acres 12/23/2022 PRE-DEVELOPMENTApplicable Standards: Urban Hydrology for Small Watersheds, Techincal Release 55. USDA, June 1986 South Broadway Pre Development Weighted CN R. Rubado Area (feet2) #1 16,203 sq. feet = 0.372 acres = Drainage Area Land Use Area (feet2) Land Use / Cover Description Hydrologic Soil Group Actual CN Weighted CN A A 0.001 sq. miles Factored CN 91 39 98 U.S. ROUTE 9 BROADWAY LINCOLN AVENUE III. Proposed Stormwater Conditions: Proposed Conditions Summary: The proposed development is designed to mimic the existing drainage patterns and reduce the discharge flow rate from the pre-developed to post-developed condition. Per the requirements set forth in the NYSDEC Stormwater Design Manual, this project classifies as a redevelopment activity with an increase in impervious cover. There is currently 20,357 sq. ft. of impervious coverage on the existing site. The proposed development will consist of 23,524 sq. ft. of impervious cover resulting in 3,167 sq. ft. of new impervious coverage. Per the Unified Development Ordinance (UDO) of Saratoga Springs, Article 17, “Post-construction requirements are limited to 100% of the Runoff Reduction volume (RRv) from new impervious cover and 50% of the RRv from existing/redeveloped imperious cover using accepted RRv criteria and methods as prescribed by the New York State Stormwater Management Design Manual.” Therefore 50% of the existing 20,357 square feet or 10,179 sq. ft. impervious area and 3,167 sq. ft. of new impervious area is required to be treated using NYSDEC accepted RRv criteria and methods. The proposed stormwater management system meets this objective by exceeding these requirements by treating 23,524 sq. ft. of impervious area in a standard practice (Infiltration Treatment System) designed per NYSDEC requirements. The proposed plan separates the site into four (4) watersheds designated as DA1, DA2, DA3, and DA4 in this report. These watersheds utilize the same discharge points as the existing conditions. The proposed Watershed Area, DA1, has been broken down into two (2) smaller subcatchment areas, DA1a and DA1b, that both discharge to DP1. DA1 includes the vast majority (85%) of the proposed re-development area. DA1a is the majority (89%) of the DA1 watershed area. This watershed is collected in four (4) on site catch basins connected via subsurface storm pipe and discharge to an on-site subsurface infiltration system. Due to fuel service proposed on-site, the site is classified by the NYSDEC as a “hot spot” and therefore requires redundant pre- treatment prior to infiltration. All stormwater tributary to the infiltration system is routed through an oil/water separator and a hydrodynamic First Defense Stormwater Treatment Unit to satisfy the redundant pre-treatment requirement. The infiltration system is designed to treat 100% of the Water Quality Volume (WQv) for Watershed Area DA1 thus satisfying all WQv and Runoff Reduction Volume (RRv) requirements for the “new” pavement proposed for this redevelopment project. The system has an overflow pipe to the city drainage structure on South Broadway to discharge water in the event of a storm greater than the 100-year storm. DA1b is a small area that is comprised of 65% grass and 35% impervious. This area sheet flows easterly to South Broadway to the same drainage structure described in DA1. Similar to the existing Watershed Area, DA2, the proposed Watershed Area, DA2, includes a small portion of the site along the Lincoln Ave. ROW. Due to the proposed grading on-site along the Lincoln Ave. ROW, the tributary area has been reduced in size and subsequently peak flows will also be reduced. This area will continue to sheet flow in a westerly direction to the same Lincoln Ave. drainage structure described above in the Existing Watershed DA1 summary. The proposed Watershed Area, DA3, is a small area consisting of the remaining portion of pre-development area DA3. This area is comprised of 100% grass that will surface flow to discharge point 3 similar to pre-development conditions with reduced flows. The proposed watershed area and topography are illustrated on the Proposed Watershed Plan included on the next page of this report. Project #Sheet # 1 of 1 Page # 1 of 2 Created By:Date: Checked By:Date: Project:Revised By:Date: Subject:Checked By:Date: %CN 22,328 Paved Parking, Roof, etc.92% 90.6 1,835 Lawn Area, Good 8% 3.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 24,163 100% %CN 1,725 Parking Lots, Roofs, etc.65% 64.0 916 Lawn Area, Good 35% 13.5 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 2,641 100% %CN 1,196 Parking Lots, Roofs, etc.41% 40.6 1,691 Lawn Area, Good 59% 22.8 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 0% 0.0 2,887 100% 94 98 39 Area (feet2) #1a + #1b 24,163 sq. feet = 0.555 acres = Drainage Area Land Use Area (feet2) Land Use / Cover Description Hydrologic Soil Group Actual CN Weighted CN A A 0.001 sq. miles Factored CN 12/23/2022 POST-DEVELOPMENTApplicable Standards: Urban Hydrology for Small Watersheds, Techincal Release 55. USDA, June 1986 South Broadway Post Development Weighted CN R. Rubado Area (feet2) Factored CN Weighted CN #2 A982,641 78 A39sq. feet = Area Land Use Area (feet2) Land Use / Cover Description Hydrologic Soil Group Actual CN acres 0.061 0.000 sq. miles = Area Land Use Area (feet2) Land Use / Cover Description Hydrologic Soil Group Actual CN Area (feet2) Factored CN Weighted CN #3 A982,887 63 A39sq. feet = sq. miles 0.000 = 0.066 acres U.S. ROUTE 9 BROADWAY LINCOLN AVENUE Conclusion: The proposed development has been designed to release stormwater at a rate not to exceed the existing condition for all subject storm events. The facility is designed to provide stormwater discharge control and quality treatment. The stormwater management system is designed to meet the objectives set forth in the NYSDEC Stormwater Management Design Manual. Uniform sizing criteria were calculated as follows: The 90% Rule Water Quality Volume (WQv) treatment is provided with a combination of hydrodynamic and infiltration treatment practices. The minimum Runoff Reduction Volume (RRv) has been achieved with the proposed on- site infiltration system. Channel Protection (Cpv) is not required for this redevelopment activity as there are no changes to hydrology that increase the discharge rate from the project site. Overbank Flood (Qp) protection was designed to control the peak discharge from the 10-year storm to the 10-year predevelopment rates. These calculations can be found in the 10-year storm analysis for each watershed and the total site volume comparison included in the report. Extreme Storm (Qf) protection was designed to control the peak discharge from the 100-year storm to the 100-year predevelopment rates and safely pass the 100-year storm event. These calculations can be found in the 100-year storm analysis for each watershed and the total site volume comparison included in the report. The proposed stormwater management system as designed will serve to mitigate the effects of the development of the parcel, such that the proposed use will not adversely affect any downstream or adjacent properties. PRE-DEVELOPMENT PEAK DISCHARGE (CFS) 1 YEAR STORM EVENT POST-DEVELOPMENT PEAK DISCHARGE (CFS) 0.81 0.00 10 YEAR 100 YEAR % REDUCTION PRE TO POST 100% WATERSHED 1 - PRE-DEVELOPMENT AND POST DEVELOPMENT STORM WATER DISCHARGE COMPARISON TABLE 1.57 0.05 97 % 2.84 0.19 93 % PRE-DEVELOPMENT PEAK DISCHARGE (CFS) 1 YEAR STORM EVENT POST-DEVELOPMENT PEAK DISCHARGE (CFS) 10 YEAR 100 YEAR % REDUCTION PRE TO POST WATERSHED 2 - PRE-DEVELOPMENT AND POST DEVELOPMENT STORM WATER DISCHARGE COMPARISON TABLE PRE-DEVELOPMENT PEAK DISCHARGE (CFS) 1 YEAR STORM EVENT POST-DEVELOPMENT PEAK DISCHARGE (CFS) 10 YEAR 100 YEAR % REDUCTION PRE TO POST WATERSHED 3 - PRE-DEVELOPMENT AND POST DEVELOPMENT STORM WATER DISCHARGE COMPARISON TABLE 0.08 0.01 88% 0.19 0.07 63% 0.48 0.24 50% 0.00 0.00 0% 0.17 0.00 100% 0.64 0.01 98% Project #Sheet # 1 of 1 Page # 1 of 1 Created By:Date: Checked By: Date: Project: Revised By: Date: Subject: Checked By: Date: Rainfall Distribution Type: 2 (1, 1A, 2 or 3) 90% Storm Event (P): 1.1 inches Weighted Hydrologic Soil Group (HSG): A (A, B, C or D) Redevelopment Project: 1 (Yes = 1, No = 2) New Impervious Cover Within Watershed Area: 0.087 Existing Impervious Cover Within Watershed Area: 0.405 Total Impervious Cover: 0.492 Impervious Area for WQv Calculation (New Const): NA Impervious Area for WQv Calculation (Redevelopment): 0.290 0.494 acres I = Impervious Area / Total Watershed Area: 0.586 I = 58.6 % Compute Runoff Coefficient, Rv Rv = 0.05 + 0.009 (I) Rv = 0.58 (Min Rv = 0.20, use 0.58 ) Compute WQv, (Includes both on-site and off-site drainage) (Use the 90% capture rule, Figure 4.1 NYS-SWDM) WQv = WQv =ac-ft = ft 3 Cell requires a direct entry 12 0.026 1139 South Broadway (P)(Rv)(A) WATER QUALITY VOLUME Computation of Preliminary Stormwater Storage Volumes and Peak Discharges (Designed for compliance with New York State Stormwater Management Design Manual) Hydrologic Input Parameters and Site Hydrology Water Quality Volume, WQv Compute Impervious Cover Total Watershed Area: R. Rubado 12/22/2022 Project #Sheet # 1 of 1 Page # 1 of 1 Created By:Date: Checked By:Date: Project:Revised By:Date: Subject:Checked By:Date: One-year Storm Event (P) =2.24 acres =sq. miles Weighted CN for this post-development drainage area: 98 = Calculated time of concentration, Tc = 0.10 ac-ft Calculate the initial absraction, Ia = (200 / CN) -2 =cubic in. Ia = 0.04 in. Calculate Ia/P = 0.02 qu = 1,000 csm/in (where csm = cubic feet per second per square mile per year) Qp = qu x A x WQv Where: Qp = (1000 csm/in) (0.0014 sq. mi.) (0.297 in.)Qp = peak discharge (cfs) Qp =0.49 cfs qu =unit peak discharge (cfs/mi2/inch) A = drainage area (square miles) WQv = water quality volume (watershed inches) From Appendix B.2 of the NYSDEC SWDM: Cell requires a direct entry Determine qu based on Tc and Ia/P Calculated WQv = 0.026 (See Exhibit B.1) 1,957,020 WQv (in inches) = 0.632 3,098,862 square in. WQv Peak Flow - DA1 Computation of Preliminary Stormwater Storage Volumes and Peak Discharges (Designed for compliance with New York State Stormwater Management Design Manual) Determination of qu Total Drainage Area = 0.494 0.0008 R. Rubado 12/23/2022 South Broadway DA1 DA1 DA2a DA2a DA2b DA2b DA3 DA3 DP1 CITY CB, BROADWAY DP2 LINCOLN AVE. DP3 NEIGHBOR PARCEL CB1 CB Existing CB CB2 CB Existing CB DW DW Routing Diagram for South Broadway-Pre Prepared by Stewart's Shops, Printed 1/12/2023 HydroCAD® 10.10-7c s/n 12543 © 2022 HydroCAD Software Solutions LLC Subcat Reach Pond Link Stewart's Shops‐South Broadway‐Predevelopment South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 2HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment‐numbers) 0.183 39 >75% Grass cover, Good, HSG A  (DA1, DA2a, DA2b, DA3) 0.001 76 Gravel roads, HSG A  (DA3) 0.332 98 Paved parking, HSG A  (DA1, DA2a, DA2b, DA3) 0.135 98 Roofs, HSG A  (DA1, DA3) 0.650 81 TOTAL AREA Stewart's Shops‐South Broadway‐Predevelopment South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 3HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 0.650 HSG A DA1, DA2a, DA2b, DA3 0.000 HSG B 0.000 HSG C 0.000 HSG D 0.000 Other 0.650 TOTAL AREA Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 4HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Time span=0.00‐24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN Reach routing by Stor‐Ind+Trans method  ‐  Pond routing by Stor‐Ind method Runoff Area=16,203 sf   87.79% Impervious   Runoff Depth>1.37"Subcatchment DA1: DA1    Flow Length=154'   Tc=8.6 min   CN=91   Runoff=0.81 cfs  0.043 af Runoff Area=2,227 sf   81.86% Impervious   Runoff Depth>1.10"Subcatchment DA2a: DA2a    Tc=6.0 min   CN=87   Runoff=0.10 cfs  0.005 af Runoff Area=2,656 sf   70.52% Impervious   Runoff Depth>0.76"Subcatchment DA2b: DA2b    Flow Length=141'   Tc=7.6 min   CN=81   Runoff=0.08 cfs  0.004 af Runoff Area=7,234 sf   33.26% Impervious   Runoff Depth>0.09"Subcatchment DA3: DA3    Tc=6.0 min   CN=59   Runoff=0.00 cfs  0.001 af    Inflow=0.81 cfs  0.043 afReach DP1: CITY CB, BROADWAY    Outflow=0.81 cfs  0.043 af    Inflow=0.08 cfs  0.004 afReach DP2: LINCOLN AVE.    Outflow=0.08 cfs  0.004 af    Inflow=0.00 cfs  0.001 afReach DP3: NEIGHBOR PARCEL    Outflow=0.00 cfs  0.001 af Peak Elev=310.09'   Inflow=0.81 cfs  0.043 afPond CB1: Existing CB 12.0"  Round Culvert  n=0.025  L=73.0'  S=0.0027 '/'   Outflow=0.81 cfs  0.043 af Peak Elev=310.72'   Inflow=0.81 cfs  0.043 afPond CB2: Existing CB 12.0"  Round Culvert  n=0.025  L=38.0'  S=0.0342 '/'   Outflow=0.81 cfs  0.043 af Peak Elev=309.91'  Storage=32 cf   Inflow=0.10 cfs  0.005 afPond DW: DW    Discarded=0.04 cfs  0.005 af   Secondary=0.00 cfs  0.000 af   Outflow=0.04 cfs  0.005 af Total Runoff Area = 0.650 ac   Runoff Volume = 0.052 af   Average Runoff Depth = 0.97" 28.22% Pervious = 0.183 ac     71.78% Impervious = 0.467 ac Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 5HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1: DA1 Runoff = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af,  Depth> 1.37"      Routed to Pond CB1 : Existing CB Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  1  yr Rainfall=2.24" Area (sf) CN Description 1,978 39 >75% Grass cover, Good, HSG A 10,061 98 Paved parking, HSG A 4,164 98 Roofs, HSG A 16,203 91 Weighted Average 1,978 12.21% Pervious Area 14,225 87.79% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.5 47 0.0280 0.10 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 0.9 70 0.0030 1.29 1.01 Pipe Channel,  12.0"  Round  Area= 0.8 sf  Perim= 3.1'  r= 0.25' n= 0.025  Corrugated metal 0.2 37 0.0160 2.98 2.34 Pipe Channel,  12.0"  Round  Area= 0.8 sf  Perim= 3.1'  r= 0.25' n= 0.025  Corrugated metal 8.6 154 Total Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 6HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA1: DA1 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type II 24-hr 1 yr Rainfall=2.24" Runoff Area=16,203 sf Runoff Volume=0.043 af Runoff Depth>1.37" Flow Length=154' Tc=8.6 min CN=91 0.81 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 7HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2a: DA2a Runoff = 0.10 cfs @ 11.97 hrs,  Volume= 0.005 af,  Depth> 1.10"      Routed to Pond DW : DW Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  1  yr Rainfall=2.24" Area (sf) CN Description 404 39 >75% Grass cover, Good, HSG A 1,823 98 Paved parking, HSG A 2,227 87 Weighted Average 404 18.14% Pervious Area 1,823 81.86% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA2a: DA2a Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.105 0.1 0.095 0.09 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type II 24-hr 1 yr Rainfall=2.24" Runoff Area=2,227 sf Runoff Volume=0.005 af Runoff Depth>1.10" Tc=6.0 min CN=87 0.10 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 8HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2b: DA2b Runoff = 0.08 cfs @ 12.00 hrs,  Volume= 0.004 af,  Depth> 0.76"      Routed to Reach DP2 : LINCOLN AVE. Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  1  yr Rainfall=2.24" Area (sf) CN Description 783 39 >75% Grass cover, Good, HSG A 1,873 98 Paved parking, HSG A 2,656 81 Weighted Average 783 29.48% Pervious Area 1,873 70.52% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.7 11 0.0210 0.07 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 0.3 16 0.0210 0.88 Sheet Flow,  Smooth surfaces   n= 0.011   P2= 2.61" 3.6 16 0.0210 0.07 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 1.0 98 0.0070 1.70 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 7.6 141 Total Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 9HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA2b: DA2b Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type II 24-hr 1 yr Rainfall=2.24" Runoff Area=2,656 sf Runoff Volume=0.004 af Runoff Depth>0.76" Flow Length=141' Tc=7.6 min CN=81 0.08 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 10HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA3: DA3 Runoff = 0.00 cfs @ 12.35 hrs,  Volume= 0.001 af,  Depth> 0.09"      Routed to Reach DP3 : NEIGHBOR PARCEL Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  1  yr Rainfall=2.24" Area (sf) CN Description 4,798 39 >75% Grass cover, Good, HSG A 1,703 98 Roofs, HSG A 30 76 Gravel roads, HSG A 703 98 Paved parking, HSG A 7,234 59 Weighted Average 4,828 66.74% Pervious Area 2,406 33.26% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA3: DA3 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.003 0.003 0.003 0.002 0.002 0.002 0.002 0.002 0.001 0.001 0.001 0.001 0.001 0.000 0.000 0 Type II 24-hr 1 yr Rainfall=2.24" Runoff Area=7,234 sf Runoff Volume=0.001 af Runoff Depth>0.09" Tc=6.0 min CN=59 0.00 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 11HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP1: CITY CB, BROADWAY Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 1.37"    for  1  yr event Inflow = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af Outflow = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP1: CITY CB, BROADWAY Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.372 ac 0.81 cfs0.81 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 12HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP2: LINCOLN AVE. Inflow Area = 0.061 ac, 70.52% Impervious,  Inflow Depth > 0.76"    for  1  yr event Inflow = 0.08 cfs @ 12.00 hrs,  Volume= 0.004 af Outflow = 0.08 cfs @ 12.00 hrs,  Volume= 0.004 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP2: LINCOLN AVE. Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Inflow Area=0.061 ac 0.08 cfs0.08 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 13HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP3: NEIGHBOR PARCEL Inflow Area = 0.166 ac, 33.26% Impervious,  Inflow Depth > 0.09"    for  1  yr event Inflow = 0.00 cfs @ 12.35 hrs,  Volume= 0.001 af Outflow = 0.00 cfs @ 12.35 hrs,  Volume= 0.001 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP3: NEIGHBOR PARCEL Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.003 0.003 0.003 0.002 0.002 0.002 0.002 0.002 0.001 0.001 0.001 0.001 0.001 0.000 0.000 0 Inflow Area=0.166 ac 0.00 cfs0.00 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 14HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond CB1: Existing CB Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 1.37"    for  1  yr event Inflow = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af Outflow = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af,  Atten= 0%,  Lag= 0.0 min Primary = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af      Routed to Pond CB2 : Existing CB Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Peak Elev= 310.09' @ 12.00 hrs Device Routing     Invert Outlet Devices #1 Primary 309.30'12.0"  Round Culvert   L= 73.0'   CMP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 309.30' / 309.10'   S= 0.0027 '/'   Cc= 0.900    n= 0.025  Corrugated metal,  Flow Area= 0.79 sf    Primary OutFlow  Max=0.80 cfs @ 12.00 hrs  HW=310.09'   (Free Discharge) 1=Culvert  (Barrel Controls 0.80 cfs @ 1.66 fps) Pond CB1: Existing CB Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.372 ac Peak Elev=310.09' 12.0" Round Culvert n=0.025 L=73.0' S=0.0027 '/' 0.81 cfs0.81 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 15HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond CB2: Existing CB Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 1.37"    for  1  yr event Inflow = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af Outflow = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af,  Atten= 0%,  Lag= 0.0 min Primary = 0.81 cfs @ 12.00 hrs,  Volume= 0.043 af      Routed to Reach DP1 : CITY CB, BROADWAY Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Peak Elev= 310.72' @ 12.00 hrs Device Routing     Invert Outlet Devices #1 Primary 310.20'12.0"  Round Culvert   L= 38.0'   CMP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 310.20' / 308.90'   S= 0.0342 '/'   Cc= 0.900    n= 0.025  Corrugated metal,  Flow Area= 0.79 sf    Primary OutFlow  Max=0.80 cfs @ 12.00 hrs  HW=310.72'   (Free Discharge) 1=Culvert  (Inlet Controls 0.80 cfs @ 1.94 fps) Pond CB2: Existing CB Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.372 ac Peak Elev=310.72' 12.0" Round Culvert n=0.025 L=38.0' S=0.0342 '/' 0.81 cfs0.81 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 16HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond DW: DW Inflow Area = 0.051 ac, 81.86% Impervious,  Inflow Depth > 1.10"    for  1  yr event Inflow = 0.10 cfs @ 11.97 hrs,  Volume= 0.005 af Outflow = 0.04 cfs @ 12.08 hrs,  Volume= 0.005 af,  Atten= 54%,  Lag= 6.3 min Discarded = 0.04 cfs @ 12.08 hrs,  Volume= 0.005 af Secondary = 0.00 cfs @ 0.00 hrs,  Volume= 0.000 af      Routed to Reach DP2 : LINCOLN AVE. Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs / 4 Peak Elev= 309.91' @ 12.08 hrs   Surf.Area= 87 sf   Storage= 32 cf Plug‐Flow detention time= 3.9 min calculated for 0.005 af (100% of inflow) Center‐of‐Mass det. time= 3.6 min ( 834.5 ‐ 830.9 ) Volume Invert Avail.Storage Storage Description #1 309.03' 102 cf Stone (Conic) Listed below (Recalc) 282 cf Overall ‐ 26 cf Embedded = 256 cf  x 40.0% Voids #2 309.73' 24 cf Drywell (Conic) Listed below (Recalc)  Inside #1 #3 311.60' 2 cf Cover (Conic) Listed below (Recalc)  Inside #1 #4 312.60' 1 cf 2.00'D x 0.33'H Vertical Cone/Cylinder ‐Impervious 130 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 309.03 87 0 0 87 312.27 87 282 282 194 Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 309.73 13 0 0 13 311.60 13 24 24 37 Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 311.60 3003 312.27 3227 Device Routing     Invert Outlet Devices #1 Discarded 309.03'15.000 in/hr Exfiltration over Wetted area    Conductivity to Groundwater Elevation = 300.75'    #2 Secondary 312.60'24.0" Horiz. Orifice/Grate    C= 0.600    Discarded OutFlow  Max=0.04 cfs @ 12.08 hrs  HW=309.90'   (Free Discharge) 1=Exfiltration  ( Controls 0.04 cfs) Secondary OutFlow  Max=0.00 cfs @ 0.00 hrs  HW=309.03'   (Free Discharge) 2=Orifice/Grate  ( Controls 0.00 cfs) Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 17HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond DW: DW Inflow Outflow Discarded Secondary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.105 0.1 0.095 0.09 0.085 0.08 0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Inflow Area=0.051 ac Peak Elev=309.91' Storage=32 cf 0.10 cfs 0.04 cfs0.04 cfs 0.00 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 18HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Time span=0.00‐24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN Reach routing by Stor‐Ind+Trans method  ‐  Pond routing by Stor‐Ind method Runoff Area=16,203 sf   87.79% Impervious   Runoff Depth>2.76"Subcatchment DA1: DA1    Flow Length=154'   Tc=8.6 min   CN=91   Runoff=1.57 cfs  0.085 af Runoff Area=2,227 sf   81.86% Impervious   Runoff Depth>2.39"Subcatchment DA2a: DA2a    Tc=6.0 min   CN=87   Runoff=0.21 cfs  0.010 af Runoff Area=2,656 sf   70.52% Impervious   Runoff Depth>1.89"Subcatchment DA2b: DA2b    Flow Length=141'   Tc=7.6 min   CN=81   Runoff=0.19 cfs  0.010 af Runoff Area=7,234 sf   33.26% Impervious   Runoff Depth>0.59"Subcatchment DA3: DA3    Tc=6.0 min   CN=59   Runoff=0.14 cfs  0.008 af    Inflow=1.57 cfs  0.085 afReach DP1: CITY CB, BROADWAY    Outflow=1.57 cfs  0.085 af    Inflow=0.19 cfs  0.010 afReach DP2: LINCOLN AVE.    Outflow=0.19 cfs  0.010 af    Inflow=0.14 cfs  0.008 afReach DP3: NEIGHBOR PARCEL    Outflow=0.14 cfs  0.008 af Peak Elev=310.74'   Inflow=1.57 cfs  0.085 afPond CB1: Existing CB 12.0"  Round Culvert  n=0.025  L=73.0'  S=0.0027 '/'   Outflow=1.57 cfs  0.085 af Peak Elev=310.98'   Inflow=1.57 cfs  0.085 afPond CB2: Existing CB 12.0"  Round Culvert  n=0.025  L=38.0'  S=0.0342 '/'   Outflow=1.57 cfs  0.085 af Peak Elev=311.65'  Storage=106 cf   Inflow=0.21 cfs  0.010 afPond DW: DW    Discarded=0.07 cfs  0.010 af   Secondary=0.00 cfs  0.000 af   Outflow=0.07 cfs  0.010 af Total Runoff Area = 0.650 ac   Runoff Volume = 0.113 af   Average Runoff Depth = 2.09" 28.22% Pervious = 0.183 ac     71.78% Impervious = 0.467 ac Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 19HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1: DA1 Runoff = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af,  Depth> 2.76"      Routed to Pond CB1 : Existing CB Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  10  yr Rainfall=3.73" Area (sf) CN Description 1,978 39 >75% Grass cover, Good, HSG A 10,061 98 Paved parking, HSG A 4,164 98 Roofs, HSG A 16,203 91 Weighted Average 1,978 12.21% Pervious Area 14,225 87.79% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.5 47 0.0280 0.10 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 0.9 70 0.0030 1.29 1.01 Pipe Channel,  12.0"  Round  Area= 0.8 sf  Perim= 3.1'  r= 0.25' n= 0.025  Corrugated metal 0.2 37 0.0160 2.98 2.34 Pipe Channel,  12.0"  Round  Area= 0.8 sf  Perim= 3.1'  r= 0.25' n= 0.025  Corrugated metal 8.6 154 Total Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 20HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA1: DA1 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)1 0 Type II 24-hr 10 yr Rainfall=3.73" Runoff Area=16,203 sf Runoff Volume=0.085 af Runoff Depth>2.76" Flow Length=154' Tc=8.6 min CN=91 1.57 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 21HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2a: DA2a Runoff = 0.21 cfs @ 11.97 hrs,  Volume= 0.010 af,  Depth> 2.39"      Routed to Pond DW : DW Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  10  yr Rainfall=3.73" Area (sf) CN Description 404 39 >75% Grass cover, Good, HSG A 1,823 98 Paved parking, HSG A 2,227 87 Weighted Average 404 18.14% Pervious Area 1,823 81.86% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA2a: DA2a Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.23 0.22 0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type II 24-hr 10 yr Rainfall=3.73" Runoff Area=2,227 sf Runoff Volume=0.010 af Runoff Depth>2.39" Tc=6.0 min CN=87 0.21 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 22HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2b: DA2b Runoff = 0.19 cfs @ 11.99 hrs,  Volume= 0.010 af,  Depth> 1.89"      Routed to Reach DP2 : LINCOLN AVE. Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  10  yr Rainfall=3.73" Area (sf) CN Description 783 39 >75% Grass cover, Good, HSG A 1,873 98 Paved parking, HSG A 2,656 81 Weighted Average 783 29.48% Pervious Area 1,873 70.52% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.7 11 0.0210 0.07 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 0.3 16 0.0210 0.88 Sheet Flow,  Smooth surfaces   n= 0.011   P2= 2.61" 3.6 16 0.0210 0.07 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 1.0 98 0.0070 1.70 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 7.6 141 Total Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 23HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA2b: DA2b Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type II 24-hr 10 yr Rainfall=3.73" Runoff Area=2,656 sf Runoff Volume=0.010 af Runoff Depth>1.89" Flow Length=141' Tc=7.6 min CN=81 0.19 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 24HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA3: DA3 Runoff = 0.14 cfs @ 11.99 hrs,  Volume= 0.008 af,  Depth> 0.59"      Routed to Reach DP3 : NEIGHBOR PARCEL Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  10  yr Rainfall=3.73" Area (sf) CN Description 4,798 39 >75% Grass cover, Good, HSG A 1,703 98 Roofs, HSG A 30 76 Gravel roads, HSG A 703 98 Paved parking, HSG A 7,234 59 Weighted Average 4,828 66.74% Pervious Area 2,406 33.26% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA3: DA3 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type II 24-hr 10 yr Rainfall=3.73" Runoff Area=7,234 sf Runoff Volume=0.008 af Runoff Depth>0.59" Tc=6.0 min CN=59 0.14 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 25HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP1: CITY CB, BROADWAY Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 2.76"    for  10  yr event Inflow = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af Outflow = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP1: CITY CB, BROADWAY Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)1 0 Inflow Area=0.372 ac 1.57 cfs1.57 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 26HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP2: LINCOLN AVE. Inflow Area = 0.061 ac, 70.52% Impervious,  Inflow Depth > 1.89"    for  10  yr event Inflow = 0.19 cfs @ 11.99 hrs,  Volume= 0.010 af Outflow = 0.19 cfs @ 11.99 hrs,  Volume= 0.010 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP2: LINCOLN AVE. Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=0.061 ac 0.19 cfs0.19 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 27HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP3: NEIGHBOR PARCEL Inflow Area = 0.166 ac, 33.26% Impervious,  Inflow Depth > 0.59"    for  10  yr event Inflow = 0.14 cfs @ 11.99 hrs,  Volume= 0.008 af Outflow = 0.14 cfs @ 11.99 hrs,  Volume= 0.008 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP3: NEIGHBOR PARCEL Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=0.166 ac 0.14 cfs0.14 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 28HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond CB1: Existing CB Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 2.76"    for  10  yr event Inflow = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af Outflow = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af,  Atten= 0%,  Lag= 0.0 min Primary = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af      Routed to Pond CB2 : Existing CB Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Peak Elev= 310.74' @ 12.00 hrs Device Routing     Invert Outlet Devices #1 Primary 309.30'12.0"  Round Culvert   L= 73.0'   CMP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 309.30' / 309.10'   S= 0.0027 '/'   Cc= 0.900    n= 0.025  Corrugated metal,  Flow Area= 0.79 sf    Primary OutFlow  Max=1.54 cfs @ 12.00 hrs  HW=310.72'   (Free Discharge) 1=Culvert  (Barrel Controls 1.54 cfs @ 1.96 fps) Pond CB1: Existing CB Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)1 0 Inflow Area=0.372 ac Peak Elev=310.74' 12.0" Round Culvert n=0.025 L=73.0' S=0.0027 '/' 1.57 cfs1.57 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 29HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond CB2: Existing CB Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 2.76"    for  10  yr event Inflow = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af Outflow = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af,  Atten= 0%,  Lag= 0.0 min Primary = 1.57 cfs @ 12.00 hrs,  Volume= 0.085 af      Routed to Reach DP1 : CITY CB, BROADWAY Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Peak Elev= 310.98' @ 12.00 hrs Device Routing     Invert Outlet Devices #1 Primary 310.20'12.0"  Round Culvert   L= 38.0'   CMP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 310.20' / 308.90'   S= 0.0342 '/'   Cc= 0.900    n= 0.025  Corrugated metal,  Flow Area= 0.79 sf    Primary OutFlow  Max=1.55 cfs @ 12.00 hrs  HW=310.98'   (Free Discharge) 1=Culvert  (Inlet Controls 1.55 cfs @ 2.37 fps) Pond CB2: Existing CB Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)1 0 Inflow Area=0.372 ac Peak Elev=310.98' 12.0" Round Culvert n=0.025 L=38.0' S=0.0342 '/' 1.57 cfs1.57 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 30HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond DW: DW Inflow Area = 0.051 ac, 81.86% Impervious,  Inflow Depth > 2.39"    for  10  yr event Inflow = 0.21 cfs @ 11.97 hrs,  Volume= 0.010 af Outflow = 0.07 cfs @ 12.10 hrs,  Volume= 0.010 af,  Atten= 64%,  Lag= 7.8 min Discarded = 0.07 cfs @ 12.10 hrs,  Volume= 0.010 af Secondary = 0.00 cfs @ 0.00 hrs,  Volume= 0.000 af      Routed to Reach DP2 : LINCOLN AVE. Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs / 4 Peak Elev= 311.65' @ 12.10 hrs   Surf.Area= 87 sf   Storage= 106 cf Plug‐Flow detention time= 10.1 min calculated for 0.010 af (100% of inflow) Center‐of‐Mass det. time= 9.1 min ( 817.9 ‐ 808.8 ) Volume Invert Avail.Storage Storage Description #1 309.03' 102 cf Stone (Conic) Listed below (Recalc) 282 cf Overall ‐ 26 cf Embedded = 256 cf  x 40.0% Voids #2 309.73' 24 cf Drywell (Conic) Listed below (Recalc)  Inside #1 #3 311.60' 2 cf Cover (Conic) Listed below (Recalc)  Inside #1 #4 312.60' 1 cf 2.00'D x 0.33'H Vertical Cone/Cylinder ‐Impervious 130 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 309.03 87 0 0 87 312.27 87 282 282 194 Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 309.73 13 0 0 13 311.60 13 24 24 37 Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 311.60 3003 312.27 3227 Device Routing     Invert Outlet Devices #1 Discarded 309.03'15.000 in/hr Exfiltration over Wetted area    Conductivity to Groundwater Elevation = 300.75'    #2 Secondary 312.60'24.0" Horiz. Orifice/Grate    C= 0.600    Discarded OutFlow  Max=0.07 cfs @ 12.10 hrs  HW=311.64'   (Free Discharge) 1=Exfiltration  ( Controls 0.07 cfs) Secondary OutFlow  Max=0.00 cfs @ 0.00 hrs  HW=309.03'   (Free Discharge) 2=Orifice/Grate  ( Controls 0.00 cfs) Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 31HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond DW: DW Inflow Outflow Discarded Secondary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.23 0.22 0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=0.051 ac Peak Elev=311.65' Storage=106 cf 0.21 cfs 0.07 cfs0.07 cfs 0.00 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 32HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Time span=0.00‐24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN Reach routing by Stor‐Ind+Trans method  ‐  Pond routing by Stor‐Ind method Runoff Area=16,203 sf   87.79% Impervious   Runoff Depth>5.19"Subcatchment DA1: DA1    Flow Length=154'   Tc=8.6 min   CN=91   Runoff=2.84 cfs  0.161 af Runoff Area=2,227 sf   81.86% Impervious   Runoff Depth>4.74"Subcatchment DA2a: DA2a    Tc=6.0 min   CN=87   Runoff=0.39 cfs  0.020 af Runoff Area=2,656 sf   70.52% Impervious   Runoff Depth>4.10"Subcatchment DA2b: DA2b    Flow Length=141'   Tc=7.6 min   CN=81   Runoff=0.40 cfs  0.021 af Runoff Area=7,234 sf   33.26% Impervious   Runoff Depth>1.99"Subcatchment DA3: DA3    Tc=6.0 min   CN=59   Runoff=0.57 cfs  0.028 af    Inflow=2.84 cfs  0.161 afReach DP1: CITY CB, BROADWAY    Outflow=2.84 cfs  0.161 af    Inflow=0.48 cfs  0.021 afReach DP2: LINCOLN AVE.    Outflow=0.48 cfs  0.021 af    Inflow=0.57 cfs  0.028 afReach DP3: NEIGHBOR PARCEL    Outflow=0.57 cfs  0.028 af Peak Elev=312.21'   Inflow=2.84 cfs  0.161 afPond CB1: Existing CB 12.0"  Round Culvert  n=0.025  L=73.0'  S=0.0027 '/'   Outflow=2.84 cfs  0.161 af Peak Elev=311.60'   Inflow=2.84 cfs  0.161 afPond CB2: Existing CB 12.0"  Round Culvert  n=0.025  L=38.0'  S=0.0342 '/'   Outflow=2.84 cfs  0.161 af Peak Elev=312.72'  Storage=129 cf   Inflow=0.39 cfs  0.020 afPond DW: DW    Discarded=0.09 cfs  0.017 af   Secondary=0.09 cfs  0.001 af   Outflow=0.18 cfs  0.018 af Total Runoff Area = 0.650 ac   Runoff Volume = 0.229 af   Average Runoff Depth = 4.23" 28.22% Pervious = 0.183 ac     71.78% Impervious = 0.467 ac Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 33HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1: DA1 Runoff = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af,  Depth> 5.19"      Routed to Pond CB1 : Existing CB Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  100 yr Rainfall=6.24" Area (sf) CN Description 1,978 39 >75% Grass cover, Good, HSG A 10,061 98 Paved parking, HSG A 4,164 98 Roofs, HSG A 16,203 91 Weighted Average 1,978 12.21% Pervious Area 14,225 87.79% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 7.5 47 0.0280 0.10 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 0.9 70 0.0030 1.29 1.01 Pipe Channel,  12.0"  Round  Area= 0.8 sf  Perim= 3.1'  r= 0.25' n= 0.025  Corrugated metal 0.2 37 0.0160 2.98 2.34 Pipe Channel,  12.0"  Round  Area= 0.8 sf  Perim= 3.1'  r= 0.25' n= 0.025  Corrugated metal 8.6 154 Total Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 34HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA1: DA1 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)3 2 1 0 Type II 24-hr 100 yr Rainfall=6.24" Runoff Area=16,203 sf Runoff Volume=0.161 af Runoff Depth>5.19" Flow Length=154' Tc=8.6 min CN=91 2.84 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 35HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2a: DA2a Runoff = 0.39 cfs @ 11.96 hrs,  Volume= 0.020 af,  Depth> 4.74"      Routed to Pond DW : DW Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  100 yr Rainfall=6.24" Area (sf) CN Description 404 39 >75% Grass cover, Good, HSG A 1,823 98 Paved parking, HSG A 2,227 87 Weighted Average 404 18.14% Pervious Area 1,823 81.86% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA2a: DA2a Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type II 24-hr 100 yr Rainfall=6.24" Runoff Area=2,227 sf Runoff Volume=0.020 af Runoff Depth>4.74" Tc=6.0 min CN=87 0.39 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 36HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2b: DA2b Runoff = 0.40 cfs @ 11.99 hrs,  Volume= 0.021 af,  Depth> 4.10"      Routed to Reach DP2 : LINCOLN AVE. Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  100 yr Rainfall=6.24" Area (sf) CN Description 783 39 >75% Grass cover, Good, HSG A 1,873 98 Paved parking, HSG A 2,656 81 Weighted Average 783 29.48% Pervious Area 1,873 70.52% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.7 11 0.0210 0.07 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 0.3 16 0.0210 0.88 Sheet Flow,  Smooth surfaces   n= 0.011   P2= 2.61" 3.6 16 0.0210 0.07 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 1.0 98 0.0070 1.70 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 7.6 141 Total Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 37HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA2b: DA2b Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type II 24-hr 100 yr Rainfall=6.24" Runoff Area=2,656 sf Runoff Volume=0.021 af Runoff Depth>4.10" Flow Length=141' Tc=7.6 min CN=81 0.40 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 38HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA3: DA3 Runoff = 0.57 cfs @ 11.98 hrs,  Volume= 0.028 af,  Depth> 1.99"      Routed to Reach DP3 : NEIGHBOR PARCEL Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  100 yr Rainfall=6.24" Area (sf) CN Description 4,798 39 >75% Grass cover, Good, HSG A 1,703 98 Roofs, HSG A 30 76 Gravel roads, HSG A 703 98 Paved parking, HSG A 7,234 59 Weighted Average 4,828 66.74% Pervious Area 2,406 33.26% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA3: DA3 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Type II 24-hr 100 yr Rainfall=6.24" Runoff Area=7,234 sf Runoff Volume=0.028 af Runoff Depth>1.99" Tc=6.0 min CN=59 0.57 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 39HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP1: CITY CB, BROADWAY Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 5.19"    for  100 yr event Inflow = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af Outflow = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP1: CITY CB, BROADWAY Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)3 2 1 0 Inflow Area=0.372 ac 2.84 cfs2.84 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 40HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP2: LINCOLN AVE. Inflow Area = 0.061 ac, 70.52% Impervious,  Inflow Depth > 4.21"    for  100 yr event Inflow = 0.48 cfs @ 11.98 hrs,  Volume= 0.021 af Outflow = 0.48 cfs @ 11.98 hrs,  Volume= 0.021 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP2: LINCOLN AVE. Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.061 ac 0.48 cfs0.48 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 41HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP3: NEIGHBOR PARCEL Inflow Area = 0.166 ac, 33.26% Impervious,  Inflow Depth > 1.99"    for  100 yr event Inflow = 0.57 cfs @ 11.98 hrs,  Volume= 0.028 af Outflow = 0.57 cfs @ 11.98 hrs,  Volume= 0.028 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP3: NEIGHBOR PARCEL Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.6 0.55 0.5 0.45 0.4 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 Inflow Area=0.166 ac 0.57 cfs0.57 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 42HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond CB1: Existing CB Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 5.19"    for  100 yr event Inflow = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af Outflow = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af,  Atten= 0%,  Lag= 0.0 min Primary = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af      Routed to Pond CB2 : Existing CB Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Peak Elev= 312.21' @ 11.99 hrs Device Routing     Invert Outlet Devices #1 Primary 309.30'12.0"  Round Culvert   L= 73.0'   CMP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 309.30' / 309.10'   S= 0.0027 '/'   Cc= 0.900    n= 0.025  Corrugated metal,  Flow Area= 0.79 sf    Primary OutFlow  Max=2.80 cfs @ 11.99 hrs  HW=312.15'   (Free Discharge) 1=Culvert  (Barrel Controls 2.80 cfs @ 3.57 fps) Pond CB1: Existing CB Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)3 2 1 0 Inflow Area=0.372 ac Peak Elev=312.21' 12.0" Round Culvert n=0.025 L=73.0' S=0.0027 '/' 2.84 cfs2.84 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 43HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond CB2: Existing CB Inflow Area = 0.372 ac, 87.79% Impervious,  Inflow Depth > 5.19"    for  100 yr event Inflow = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af Outflow = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af,  Atten= 0%,  Lag= 0.0 min Primary = 2.84 cfs @ 11.99 hrs,  Volume= 0.161 af      Routed to Reach DP1 : CITY CB, BROADWAY Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Peak Elev= 311.60' @ 11.99 hrs Device Routing     Invert Outlet Devices #1 Primary 310.20'12.0"  Round Culvert   L= 38.0'   CMP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 310.20' / 308.90'   S= 0.0342 '/'   Cc= 0.900    n= 0.025  Corrugated metal,  Flow Area= 0.79 sf    Primary OutFlow  Max=2.80 cfs @ 11.99 hrs  HW=311.58'   (Free Discharge) 1=Culvert  (Inlet Controls 2.80 cfs @ 3.57 fps) Pond CB2: Existing CB Inflow Primary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)3 2 1 0 Inflow Area=0.372 ac Peak Elev=311.60' 12.0" Round Culvert n=0.025 L=38.0' S=0.0342 '/' 2.84 cfs2.84 cfs Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 44HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond DW: DW Inflow Area = 0.051 ac, 81.86% Impervious,  Inflow Depth > 4.74"    for  100 yr event Inflow = 0.39 cfs @ 11.96 hrs,  Volume= 0.020 af Outflow = 0.18 cfs @ 11.97 hrs,  Volume= 0.018 af,  Atten= 56%,  Lag= 0.1 min Discarded = 0.09 cfs @ 11.97 hrs,  Volume= 0.017 af Secondary = 0.09 cfs @ 11.97 hrs,  Volume= 0.001 af      Routed to Reach DP2 : LINCOLN AVE. Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs / 4 Peak Elev= 312.72' @ 11.97 hrs   Surf.Area= 87 sf   Storage= 129 cf Plug‐Flow detention time= 77.3 min calculated for 0.018 af (88% of inflow) Center‐of‐Mass det. time= 19.1 min ( 808.6 ‐ 789.5 ) Volume Invert Avail.Storage Storage Description #1 309.03' 102 cf Stone (Conic) Listed below (Recalc) 282 cf Overall ‐ 26 cf Embedded = 256 cf  x 40.0% Voids #2 309.73' 24 cf Drywell (Conic) Listed below (Recalc)  Inside #1 #3 311.60' 2 cf Cover (Conic) Listed below (Recalc)  Inside #1 #4 312.60' 1 cf 2.00'D x 0.33'H Vertical Cone/Cylinder ‐Impervious 130 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 309.03 87 0 0 87 312.27 87 282 282 194 Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 309.73 13 0 0 13 311.60 13 24 24 37 Elevation Surf.Area Inc.Store Cum.Store Wet.Area (feet) (sq‐ft) (cubic‐feet) (cubic‐feet) (sq‐ft) 311.60 3003 312.27 3227 Device Routing     Invert Outlet Devices #1 Discarded 309.03'15.000 in/hr Exfiltration over Wetted area    Conductivity to Groundwater Elevation = 300.75'    #2 Secondary 312.60'24.0" Horiz. Orifice/Grate    C= 0.600    Discarded OutFlow  Max=0.09 cfs @ 11.97 hrs  HW=312.60'   (Free Discharge) 1=Exfiltration  ( Controls 0.09 cfs) Secondary OutFlow  Max=0.39 cfs @ 11.97 hrs  HW=312.60'   (Free Discharge) 2=Orifice/Grate  (Orifice Controls 0.39 cfs @ 0.12 fps) Stewart's Shops‐South Broadway‐Predevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Pre   Printed  1/12/2023Prepared by Stewart's Shops Page 45HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond DW: DW Inflow Outflow Discarded Secondary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.44 0.42 0.4 0.38 0.36 0.34 0.32 0.3 0.28 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Inflow Area=0.051 ac Peak Elev=312.72' Storage=129 cf 0.39 cfs 0.18 cfs 0.09 cfs 0.09 cfs DA1a DA1a DA1b DA1b DA2 DA2 DA3 DA3 DP1 South Broadway DP2 Lincoln Ave. DP3 Neioghbor Parcel 1P Infiltration basin Routing Diagram for South Broadway-Post Prepared by Stewart's Shops, Printed 1/12/2023 HydroCAD® 10.10-7c s/n 12543 © 2022 HydroCAD Software Solutions LLC Subcat Reach Pond Link Stewart's Shops‐South Broadway‐Postdevelopment South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 2HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (acres) CN Description (subcatchment‐numbers) 0.114 39 >75% Grass cover, Good, HSG A  (DA1a, DA1b, DA2, DA3) 0.399 98 Paved parking, HSG A  (DA1a, DA1b, DA2) 0.141 98 Roofs, HSG A  (DA1a) 0.654 88 TOTAL AREA Stewart's Shops‐South Broadway‐Postdevelopment South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 3HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 0.654 HSG A DA1a, DA1b, DA2, DA3 0.000 HSG B 0.000 HSG C 0.000 HSG D 0.000 Other 0.654 TOTAL AREA Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 4HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Time span=0.00‐24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN Reach routing by Stor‐Ind+Trans method  ‐  Pond routing by Stor‐Ind method Runoff Area=21,522 sf   99.49% Impervious   Runoff Depth>2.01"Subcatchment DA1a: DA1a    Tc=6.0 min   CN=98   Runoff=1.50 cfs  0.083 af Runoff Area=2,641 sf   34.68% Impervious   Runoff Depth>0.09"Subcatchment DA1b: DA1b    Flow Length=133'   Tc=8.5 min   CN=59   Runoff=0.00 cfs  0.000 af Runoff Area=2,887 sf   41.43% Impervious   Runoff Depth>0.16"Subcatchment DA2: DA2    Flow Length=174'   Tc=9.3 min   CN=63   Runoff=0.01 cfs  0.001 af Runoff Area=1,420 sf   0.00% Impervious   Runoff Depth=0.00"Subcatchment DA3: DA3    Tc=6.0 min   CN=39   Runoff=0.00 cfs  0.000 af    Inflow=0.00 cfs  0.000 afReach DP1: South Broadway    Outflow=0.00 cfs  0.000 af    Inflow=0.01 cfs  0.001 afReach DP2: Lincoln Ave.    Outflow=0.01 cfs  0.001 af    Inflow=0.00 cfs  0.000 afReach DP3: Neioghbor Parcel    Outflow=0.00 cfs  0.000 af Peak Elev=308.48'  Storage=546 cf   Inflow=1.50 cfs  0.083 afPond 1P: Infiltration basin    Discarded=0.63 cfs  0.083 af   Secondary=0.00 cfs  0.000 af   Outflow=0.63 cfs  0.083 af Total Runoff Area = 0.654 ac   Runoff Volume = 0.084 af   Average Runoff Depth = 1.55" 17.37% Pervious = 0.114 ac     82.63% Impervious = 0.540 ac Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 5HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1a: DA1a Runoff = 1.50 cfs @ 11.96 hrs,  Volume= 0.083 af,  Depth> 2.01"      Routed to Pond 1P : Infiltration basin Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  1  yr Rainfall=2.24" Area (sf) CN Description 110 39 >75% Grass cover, Good, HSG A 15,290 98 Paved parking, HSG A 6,122 98 Roofs, HSG A 21,522 98 Weighted Average 110 0.51% Pervious Area 21,412 99.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA1a: DA1a Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)1 0 Type II 24-hr 1 yr Rainfall=2.24" Runoff Area=21,522 sf Runoff Volume=0.083 af Runoff Depth>2.01" Tc=6.0 min CN=98 1.50 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 6HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1b: DA1b Runoff = 0.00 cfs @ 12.39 hrs,  Volume= 0.000 af,  Depth> 0.09"      Routed to Reach DP1 : South Broadway Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  1  yr Rainfall=2.24" Area (sf) CN Description 1,725 39 >75% Grass cover, Good, HSG A 916 98 Paved parking, HSG A 2,641 59 Weighted Average 1,725 65.32% Pervious Area 916 34.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.2 14 0.0040 0.04 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 2.1 86 0.0020 0.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 5 0.0600 3.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 5 0.0150 2.49 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.0 5 0.0600 3.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 9 0.0420 4.16 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.2 9 0.0010 0.64 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 8.5 133 Total Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 7HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA1b: DA1b Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0 0 0 Type II 24-hr 1 yr Rainfall=2.24" Runoff Area=2,641 sf Runoff Volume=0.000 af Runoff Depth>0.09" Flow Length=133' Tc=8.5 min CN=59 0.00 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 8HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2: DA2 Runoff = 0.01 cfs @ 12.07 hrs,  Volume= 0.001 af,  Depth> 0.16"      Routed to Reach DP2 : Lincoln Ave. Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  1  yr Rainfall=2.24" Area (sf) CN Description 1,691 39 >75% Grass cover, Good, HSG A 1,196 98 Paved parking, HSG A 2,887 63 Weighted Average 1,691 58.57% Pervious Area 1,196 41.43% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.5 19 0.0100 0.06 Sheet Flow, 19' Grass: Dense   n= 0.240   P2= 2.61" 2.8 37 0.0010 0.22 Shallow Concentrated Flow,  Short Grass Pasture   Kv= 7.0 fps 0.0 5 0.0750 1.92 Shallow Concentrated Flow,  Short Grass Pasture   Kv= 7.0 fps 0.0 5 0.0150 2.49 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.0 2 0.0100 1.50 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 4 0.1220 7.09 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 1.0 102 0.0070 1.70 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 9.3 174 Total Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 9HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA2: DA2 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.007 0.007 0.006 0.005 0.005 0.004 0.004 0.003 0.003 0.002 0.002 0.001 0.001 0.000 0 Type II 24-hr 1 yr Rainfall=2.24" Runoff Area=2,887 sf Runoff Volume=0.001 af Runoff Depth>0.16" Flow Length=174' Tc=9.3 min CN=63 0.01 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 10HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA3: DA3 Runoff = 0.00 cfs @ 0.00 hrs,  Volume= 0.000 af,  Depth= 0.00"      Routed to Reach DP3 : Neioghbor Parcel Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  1  yr Rainfall=2.24" Area (sf) CN Description 1,420 39 >75% Grass cover, Good, HSG A 1,420 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, MIN Tc Subcatchment DA3: DA3 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)1 0 Type II 24-hr 1 yr Rainfall=2.24" Runoff Area=1,420 sf Runoff Volume=0.000 af Runoff Depth=0.00" Tc=6.0 min CN=39 0.00 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 11HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP1: South Broadway Inflow Area = 0.061 ac, 34.68% Impervious,  Inflow Depth > 0.09"    for  1  yr event Inflow = 0.00 cfs @ 12.39 hrs,  Volume= 0.000 af Outflow = 0.00 cfs @ 12.39 hrs,  Volume= 0.000 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP1: South Broadway Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0 0 0 Inflow Area=0.061 ac 0.00 cfs0.00 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 12HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP2: Lincoln Ave. Inflow Area = 0.066 ac, 41.43% Impervious,  Inflow Depth > 0.16"    for  1  yr event Inflow = 0.01 cfs @ 12.07 hrs,  Volume= 0.001 af Outflow = 0.01 cfs @ 12.07 hrs,  Volume= 0.001 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP2: Lincoln Ave. Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.007 0.007 0.006 0.005 0.005 0.004 0.004 0.003 0.003 0.002 0.002 0.001 0.001 0.000 0 Inflow Area=0.066 ac 0.01 cfs0.01 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 13HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP3: Neioghbor Parcel Inflow Area = 0.033 ac, 0.00% Impervious,  Inflow Depth = 0.00"    for  1  yr event Inflow = 0.00 cfs @ 0.00 hrs,  Volume= 0.000 af Outflow = 0.00 cfs @ 0.00 hrs,  Volume= 0.000 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP3: Neioghbor Parcel Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)1 0 Inflow Area=0.033 ac 0.00 cfs0.00 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 14HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond 1P: Infiltration basin Inflow Area = 0.494 ac, 99.49% Impervious,  Inflow Depth > 2.01"    for  1  yr event Inflow = 1.50 cfs @ 11.96 hrs,  Volume= 0.083 af Outflow = 0.63 cfs @ 12.08 hrs,  Volume= 0.083 af,  Atten= 58%,  Lag= 6.9 min Discarded = 0.63 cfs @ 12.08 hrs,  Volume= 0.083 af Secondary = 0.00 cfs @ 0.00 hrs,  Volume= 0.000 af      Routed to Reach DP1 : South Broadway Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs / 3 Peak Elev= 308.48' @ 12.08 hrs   Surf.Area= 1,547 sf   Storage= 546 cf Plug‐Flow detention time= 4.6 min calculated for 0.083 af (100% of inflow) Center‐of‐Mass det. time= 3.6 min ( 763.9 ‐ 760.3 ) Volume Invert Avail.Storage Storage Description #1A 307.79' 1,406 cf 25.25'W x 60.58'L x 3.50'H Field A 5,353 cf Overall ‐ 1,838 cf Embedded = 3,516 cf  x 40.0% Voids #2A 308.29' 1,838 cf ADS_StormTech SC‐740 +Cap  x 40  Inside #1 Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 40 Chambers in 5 Rows #3 308.39' 24 cf 12.0"  Round Pipe Storage L= 30.0' 3,268 cf Total Available Storage      Storage Group A created with Chamber Wizard Device Routing     Invert Outlet Devices #1 Discarded 307.79'15.000 in/hr Exfiltration over Wetted area    Conductivity to Groundwater Elevation = 300.75'    #2 Secondary 310.63'6.0"  Round Culvert   L= 26.0'   CPP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 310.63' / 308.90'   S= 0.0665 '/'   Cc= 0.900    n= 0.013  Corrugated PE, smooth interior,  Flow Area= 0.20 sf    Discarded OutFlow  Max=0.63 cfs @ 12.08 hrs  HW=308.48'   (Free Discharge) 1=Exfiltration  ( Controls 0.63 cfs) Secondary OutFlow  Max=0.00 cfs @ 0.00 hrs  HW=307.79'   (Free Discharge) 2=Culvert  ( Controls 0.00 cfs) Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 15HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond 1P: Infiltration basin ‐ Chamber Wizard Field A Chamber Model = ADS_StormTech SC‐740 +Cap (ADS StormTech® SC‐740 with cap length) Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 51.0" Wide + 6.0" Spacing = 57.0" C‐C Row Spacing 8 Chambers/Row x 7.12' Long +0.81' Cap Length x 2 = 58.58' Row Length +12.0" End Stone x 2 = 60.58' Base Length 5 Rows x 51.0" Wide + 6.0" Spacing x 4 + 12.0" Side Stone x 2 = 25.25' Base Width 6.0" Stone Base + 30.0" Chamber Height + 6.0" Stone Cover = 3.50' Field Height 40 Chambers x 45.9 cf = 1,837.6 cf Chamber Storage 5,353.5 cf Field ‐ 1,837.6 cf Chambers = 3,515.9 cf Stone x 40.0% Voids = 1,406.3 cf Stone Storage Chamber Storage + Stone Storage = 3,243.9 cf = 0.074 af Overall Storage Efficiency = 60.6% Overall System Size = 60.58' x 25.25' x 3.50' 40 Chambers 198.3 cy Field 130.2 cy Stone Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  1  yr Rainfall=2.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 16HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond 1P: Infiltration basin Inflow Outflow Discarded Secondary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)1 0 Inflow Area=0.494 ac Peak Elev=308.48' Storage=546 cf 1.50 cfs 0.63 cfs0.63 cfs 0.00 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 17HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Time span=0.00‐24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN Reach routing by Stor‐Ind+Trans method  ‐  Pond routing by Stor‐Ind method Runoff Area=21,522 sf   99.49% Impervious   Runoff Depth>3.49"Subcatchment DA1a: DA1a    Tc=6.0 min   CN=98   Runoff=2.54 cfs  0.144 af Runoff Area=2,641 sf   34.68% Impervious   Runoff Depth>0.59"Subcatchment DA1b: DA1b    Flow Length=133'   Tc=8.5 min   CN=59   Runoff=0.05 cfs  0.003 af Runoff Area=2,887 sf   41.43% Impervious   Runoff Depth>0.77"Subcatchment DA2: DA2    Flow Length=174'   Tc=9.3 min   CN=63   Runoff=0.07 cfs  0.004 af Runoff Area=1,420 sf   0.00% Impervious   Runoff Depth>0.02"Subcatchment DA3: DA3    Tc=6.0 min   CN=39   Runoff=0.00 cfs  0.000 af    Inflow=0.05 cfs  0.003 afReach DP1: South Broadway    Outflow=0.05 cfs  0.003 af    Inflow=0.07 cfs  0.004 afReach DP2: Lincoln Ave.    Outflow=0.07 cfs  0.004 af    Inflow=0.00 cfs  0.000 afReach DP3: Neioghbor Parcel    Outflow=0.00 cfs  0.000 af Peak Elev=309.16'  Storage=1,383 cf   Inflow=2.54 cfs  0.144 afPond 1P: Infiltration basin    Discarded=0.75 cfs  0.143 af   Secondary=0.00 cfs  0.000 af   Outflow=0.75 cfs  0.143 af Total Runoff Area = 0.654 ac   Runoff Volume = 0.151 af   Average Runoff Depth = 2.77" 17.37% Pervious = 0.114 ac     82.63% Impervious = 0.540 ac Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 18HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1a: DA1a Runoff = 2.54 cfs @ 11.96 hrs,  Volume= 0.144 af,  Depth> 3.49"      Routed to Pond 1P : Infiltration basin Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  10  yr Rainfall=3.73" Area (sf) CN Description 110 39 >75% Grass cover, Good, HSG A 15,290 98 Paved parking, HSG A 6,122 98 Roofs, HSG A 21,522 98 Weighted Average 110 0.51% Pervious Area 21,412 99.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA1a: DA1a Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)2 1 0 Type II 24-hr 10 yr Rainfall=3.73" Runoff Area=21,522 sf Runoff Volume=0.144 af Runoff Depth>3.49" Tc=6.0 min CN=98 2.54 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 19HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1b: DA1b Runoff = 0.05 cfs @ 12.02 hrs,  Volume= 0.003 af,  Depth> 0.59"      Routed to Reach DP1 : South Broadway Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  10  yr Rainfall=3.73" Area (sf) CN Description 1,725 39 >75% Grass cover, Good, HSG A 916 98 Paved parking, HSG A 2,641 59 Weighted Average 1,725 65.32% Pervious Area 916 34.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.2 14 0.0040 0.04 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 2.1 86 0.0020 0.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 5 0.0600 3.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 5 0.0150 2.49 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.0 5 0.0600 3.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 9 0.0420 4.16 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.2 9 0.0010 0.64 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 8.5 133 Total Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 20HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA1b: DA1b Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.05 0.048 0.046 0.044 0.042 0.04 0.038 0.036 0.034 0.032 0.03 0.028 0.026 0.024 0.022 0.02 0.018 0.016 0.014 0.012 0.01 0.008 0.006 0.004 0.002 0 Type II 24-hr 10 yr Rainfall=3.73" Runoff Area=2,641 sf Runoff Volume=0.003 af Runoff Depth>0.59" Flow Length=133' Tc=8.5 min CN=59 0.05 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 21HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2: DA2 Runoff = 0.07 cfs @ 12.03 hrs,  Volume= 0.004 af,  Depth> 0.77"      Routed to Reach DP2 : Lincoln Ave. Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  10  yr Rainfall=3.73" Area (sf) CN Description 1,691 39 >75% Grass cover, Good, HSG A 1,196 98 Paved parking, HSG A 2,887 63 Weighted Average 1,691 58.57% Pervious Area 1,196 41.43% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.5 19 0.0100 0.06 Sheet Flow, 19' Grass: Dense   n= 0.240   P2= 2.61" 2.8 37 0.0010 0.22 Shallow Concentrated Flow,  Short Grass Pasture   Kv= 7.0 fps 0.0 5 0.0750 1.92 Shallow Concentrated Flow,  Short Grass Pasture   Kv= 7.0 fps 0.0 5 0.0150 2.49 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.0 2 0.0100 1.50 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 4 0.1220 7.09 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 1.0 102 0.0070 1.70 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 9.3 174 Total Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 22HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA2: DA2 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Type II 24-hr 10 yr Rainfall=3.73" Runoff Area=2,887 sf Runoff Volume=0.004 af Runoff Depth>0.77" Flow Length=174' Tc=9.3 min CN=63 0.07 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 23HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA3: DA3 Runoff = 0.00 cfs @ 23.95 hrs,  Volume= 0.000 af,  Depth> 0.02"      Routed to Reach DP3 : Neioghbor Parcel Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  10  yr Rainfall=3.73" Area (sf) CN Description 1,420 39 >75% Grass cover, Good, HSG A 1,420 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, MIN Tc Subcatchment DA3: DA3 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.000 0.000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Type II 24-hr 10 yr Rainfall=3.73" Runoff Area=1,420 sf Runoff Volume=0.000 af Runoff Depth>0.02" Tc=6.0 min CN=39 0.00 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 24HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP1: South Broadway Inflow Area = 0.061 ac, 34.68% Impervious,  Inflow Depth > 0.59"    for  10  yr event Inflow = 0.05 cfs @ 12.02 hrs,  Volume= 0.003 af Outflow = 0.05 cfs @ 12.02 hrs,  Volume= 0.003 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP1: South Broadway Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Inflow Area=0.061 ac 0.05 cfs0.05 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 25HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP2: Lincoln Ave. Inflow Area = 0.066 ac, 41.43% Impervious,  Inflow Depth > 0.77"    for  10  yr event Inflow = 0.07 cfs @ 12.03 hrs,  Volume= 0.004 af Outflow = 0.07 cfs @ 12.03 hrs,  Volume= 0.004 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP2: Lincoln Ave. Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.075 0.07 0.065 0.06 0.055 0.05 0.045 0.04 0.035 0.03 0.025 0.02 0.015 0.01 0.005 0 Inflow Area=0.066 ac 0.07 cfs0.07 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 26HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP3: Neioghbor Parcel Inflow Area = 0.033 ac, 0.00% Impervious,  Inflow Depth > 0.02"    for  10  yr event Inflow = 0.00 cfs @ 23.95 hrs,  Volume= 0.000 af Outflow = 0.00 cfs @ 23.95 hrs,  Volume= 0.000 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP3: Neioghbor Parcel Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.000 0.000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Inflow Area=0.033 ac 0.00 cfs0.00 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 27HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond 1P: Infiltration basin Inflow Area = 0.494 ac, 99.49% Impervious,  Inflow Depth > 3.49"    for  10  yr event Inflow = 2.54 cfs @ 11.96 hrs,  Volume= 0.144 af Outflow = 0.75 cfs @ 12.11 hrs,  Volume= 0.143 af,  Atten= 71%,  Lag= 8.9 min Discarded = 0.75 cfs @ 12.11 hrs,  Volume= 0.143 af Secondary = 0.00 cfs @ 0.00 hrs,  Volume= 0.000 af      Routed to Reach DP1 : South Broadway Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs / 3 Peak Elev= 309.16' @ 12.11 hrs   Surf.Area= 1,555 sf   Storage= 1,383 cf Plug‐Flow detention time= 10.7 min calculated for 0.143 af (100% of inflow) Center‐of‐Mass det. time= 8.9 min ( 757.6 ‐ 748.8 ) Volume Invert Avail.Storage Storage Description #1A 307.79' 1,406 cf 25.25'W x 60.58'L x 3.50'H Field A 5,353 cf Overall ‐ 1,838 cf Embedded = 3,516 cf  x 40.0% Voids #2A 308.29' 1,838 cf ADS_StormTech SC‐740 +Cap  x 40  Inside #1 Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 40 Chambers in 5 Rows #3 308.39' 24 cf 12.0"  Round Pipe Storage L= 30.0' 3,268 cf Total Available Storage      Storage Group A created with Chamber Wizard Device Routing     Invert Outlet Devices #1 Discarded 307.79'15.000 in/hr Exfiltration over Wetted area    Conductivity to Groundwater Elevation = 300.75'    #2 Secondary 310.63'6.0"  Round Culvert   L= 26.0'   CPP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 310.63' / 308.90'   S= 0.0665 '/'   Cc= 0.900    n= 0.013  Corrugated PE, smooth interior,  Flow Area= 0.20 sf    Discarded OutFlow  Max=0.75 cfs @ 12.11 hrs  HW=309.15'   (Free Discharge) 1=Exfiltration  ( Controls 0.75 cfs) Secondary OutFlow  Max=0.00 cfs @ 0.00 hrs  HW=307.79'   (Free Discharge) 2=Culvert  ( Controls 0.00 cfs) Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 28HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond 1P: Infiltration basin ‐ Chamber Wizard Field A Chamber Model = ADS_StormTech SC‐740 +Cap (ADS StormTech® SC‐740 with cap length) Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 51.0" Wide + 6.0" Spacing = 57.0" C‐C Row Spacing 8 Chambers/Row x 7.12' Long +0.81' Cap Length x 2 = 58.58' Row Length +12.0" End Stone x 2 = 60.58' Base Length 5 Rows x 51.0" Wide + 6.0" Spacing x 4 + 12.0" Side Stone x 2 = 25.25' Base Width 6.0" Stone Base + 30.0" Chamber Height + 6.0" Stone Cover = 3.50' Field Height 40 Chambers x 45.9 cf = 1,837.6 cf Chamber Storage 5,353.5 cf Field ‐ 1,837.6 cf Chambers = 3,515.9 cf Stone x 40.0% Voids = 1,406.3 cf Stone Storage Chamber Storage + Stone Storage = 3,243.9 cf = 0.074 af Overall Storage Efficiency = 60.6% Overall System Size = 60.58' x 25.25' x 3.50' 40 Chambers 198.3 cy Field 130.2 cy Stone Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  10  yr Rainfall=3.73"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 29HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond 1P: Infiltration basin Inflow Outflow Discarded Secondary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)2 1 0 Inflow Area=0.494 ac Peak Elev=309.16' Storage=1,383 cf 2.54 cfs 0.75 cfs0.75 cfs 0.00 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 30HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Time span=0.00‐24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN Reach routing by Stor‐Ind+Trans method  ‐  Pond routing by Stor‐Ind method Runoff Area=21,522 sf   99.49% Impervious   Runoff Depth>6.00"Subcatchment DA1a: DA1a    Tc=6.0 min   CN=98   Runoff=4.28 cfs  0.247 af Runoff Area=2,641 sf   34.68% Impervious   Runoff Depth>1.99"Subcatchment DA1b: DA1b    Flow Length=133'   Tc=8.5 min   CN=59   Runoff=0.19 cfs  0.010 af Runoff Area=2,887 sf   41.43% Impervious   Runoff Depth>2.34"Subcatchment DA2: DA2    Flow Length=174'   Tc=9.3 min   CN=63   Runoff=0.24 cfs  0.013 af Runoff Area=1,420 sf   0.00% Impervious   Runoff Depth>0.51"Subcatchment DA3: DA3    Tc=6.0 min   CN=39   Runoff=0.01 cfs  0.001 af    Inflow=0.19 cfs  0.010 afReach DP1: South Broadway    Outflow=0.19 cfs  0.010 af    Inflow=0.24 cfs  0.013 afReach DP2: Lincoln Ave.    Outflow=0.24 cfs  0.013 af    Inflow=0.01 cfs  0.001 afReach DP3: Neioghbor Parcel    Outflow=0.01 cfs  0.001 af Peak Elev=310.65'  Storage=2,872 cf   Inflow=4.28 cfs  0.247 afPond 1P: Infiltration basin    Discarded=0.99 cfs  0.247 af   Secondary=0.00 cfs  0.000 af   Outflow=0.99 cfs  0.247 af Total Runoff Area = 0.654 ac   Runoff Volume = 0.271 af   Average Runoff Depth = 4.98" 17.37% Pervious = 0.114 ac     82.63% Impervious = 0.540 ac Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 31HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1a: DA1a Runoff = 4.28 cfs @ 11.96 hrs,  Volume= 0.247 af,  Depth> 6.00"      Routed to Pond 1P : Infiltration basin Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  100 yr Rainfall=6.24" Area (sf) CN Description 110 39 >75% Grass cover, Good, HSG A 15,290 98 Paved parking, HSG A 6,122 98 Roofs, HSG A 21,522 98 Weighted Average 110 0.51% Pervious Area 21,412 99.49% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Min. Tc Subcatchment DA1a: DA1a Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)4 3 2 1 0 Type II 24-hr 100 yr Rainfall=6.24" Runoff Area=21,522 sf Runoff Volume=0.247 af Runoff Depth>6.00" Tc=6.0 min CN=98 4.28 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 32HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA1b: DA1b Runoff = 0.19 cfs @ 12.01 hrs,  Volume= 0.010 af,  Depth> 1.99"      Routed to Reach DP1 : South Broadway Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  100 yr Rainfall=6.24" Area (sf) CN Description 1,725 39 >75% Grass cover, Good, HSG A 916 98 Paved parking, HSG A 2,641 59 Weighted Average 1,725 65.32% Pervious Area 916 34.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.2 14 0.0040 0.04 Sheet Flow,  Grass: Dense   n= 0.240   P2= 2.61" 2.1 86 0.0020 0.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 5 0.0600 3.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 5 0.0150 2.49 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.0 5 0.0600 3.67 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 9 0.0420 4.16 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.2 9 0.0010 0.64 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 8.5 133 Total Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 33HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA1b: DA1b Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Type II 24-hr 100 yr Rainfall=6.24" Runoff Area=2,641 sf Runoff Volume=0.010 af Runoff Depth>1.99" Flow Length=133' Tc=8.5 min CN=59 0.19 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 34HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA2: DA2 Runoff = 0.24 cfs @ 12.01 hrs,  Volume= 0.013 af,  Depth> 2.34"      Routed to Reach DP2 : Lincoln Ave. Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  100 yr Rainfall=6.24" Area (sf) CN Description 1,691 39 >75% Grass cover, Good, HSG A 1,196 98 Paved parking, HSG A 2,887 63 Weighted Average 1,691 58.57% Pervious Area 1,196 41.43% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.5 19 0.0100 0.06 Sheet Flow, 19' Grass: Dense   n= 0.240   P2= 2.61" 2.8 37 0.0010 0.22 Shallow Concentrated Flow,  Short Grass Pasture   Kv= 7.0 fps 0.0 5 0.0750 1.92 Shallow Concentrated Flow,  Short Grass Pasture   Kv= 7.0 fps 0.0 5 0.0150 2.49 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 0.0 2 0.0100 1.50 Shallow Concentrated Flow,  Grassed Waterway   Kv= 15.0 fps 0.0 4 0.1220 7.09 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 1.0 102 0.0070 1.70 Shallow Concentrated Flow,  Paved   Kv= 20.3 fps 9.3 174 Total Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 35HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Subcatchment DA2: DA2 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Type II 24-hr 100 yr Rainfall=6.24" Runoff Area=2,887 sf Runoff Volume=0.013 af Runoff Depth>2.34" Flow Length=174' Tc=9.3 min CN=63 0.24 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 36HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Subcatchment DA3: DA3 Runoff = 0.01 cfs @ 12.02 hrs,  Volume= 0.001 af,  Depth> 0.51"      Routed to Reach DP3 : Neioghbor Parcel Runoff by SCS TR‐20 method, UH=SCS, Weighted‐CN, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Type II 24‐hr  100 yr Rainfall=6.24" Area (sf) CN Description 1,420 39 >75% Grass cover, Good, HSG A 1,420 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, MIN Tc Subcatchment DA3: DA3 Runoff Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.016 0.015 0.014 0.013 0.012 0.011 0.01 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001 0 Type II 24-hr 100 yr Rainfall=6.24" Runoff Area=1,420 sf Runoff Volume=0.001 af Runoff Depth>0.51" Tc=6.0 min CN=39 0.01 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 37HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP1: South Broadway Inflow Area = 0.061 ac, 34.68% Impervious,  Inflow Depth > 1.99"    for  100 yr event Inflow = 0.19 cfs @ 12.01 hrs,  Volume= 0.010 af Outflow = 0.19 cfs @ 12.01 hrs,  Volume= 0.010 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP1: South Broadway Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.21 0.2 0.19 0.18 0.17 0.16 0.15 0.14 0.13 0.12 0.11 0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01 0 Inflow Area=0.061 ac 0.19 cfs0.19 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 38HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP2: Lincoln Ave. Inflow Area = 0.066 ac, 41.43% Impervious,  Inflow Depth > 2.34"    for  100 yr event Inflow = 0.24 cfs @ 12.01 hrs,  Volume= 0.013 af Outflow = 0.24 cfs @ 12.01 hrs,  Volume= 0.013 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP2: Lincoln Ave. Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 0.08 0.06 0.04 0.02 0 Inflow Area=0.066 ac 0.24 cfs0.24 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 39HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Reach DP3: Neioghbor Parcel Inflow Area = 0.033 ac, 0.00% Impervious,  Inflow Depth > 0.51"    for  100 yr event Inflow = 0.01 cfs @ 12.02 hrs,  Volume= 0.001 af Outflow = 0.01 cfs @ 12.02 hrs,  Volume= 0.001 af,  Atten= 0%,  Lag= 0.0 min Routing by Stor‐Ind+Trans method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs Reach DP3: Neioghbor Parcel Inflow Outflow Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)0.016 0.015 0.014 0.013 0.012 0.011 0.01 0.009 0.008 0.007 0.006 0.005 0.004 0.003 0.002 0.001 0 Inflow Area=0.033 ac 0.01 cfs0.01 cfs Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 40HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Summary for Pond 1P: Infiltration basin Inflow Area = 0.494 ac, 99.49% Impervious,  Inflow Depth > 6.00"    for  100 yr event Inflow = 4.28 cfs @ 11.96 hrs,  Volume= 0.247 af Outflow = 0.99 cfs @ 12.13 hrs,  Volume= 0.247 af,  Atten= 77%,  Lag= 9.9 min Discarded = 0.99 cfs @ 12.13 hrs,  Volume= 0.247 af Secondary = 0.00 cfs @ 12.13 hrs,  Volume= 0.000 af      Routed to Reach DP1 : South Broadway Routing by Stor‐Ind method, Time Span= 0.00‐24.00 hrs, dt= 0.05 hrs / 3 Peak Elev= 310.65' @ 12.13 hrs   Surf.Area= 1,530 sf   Storage= 2,872 cf Plug‐Flow detention time= (not calculated: outflow precedes inflow) Center‐of‐Mass det. time= 16.8 min ( 756.6 ‐ 739.9 ) Volume Invert Avail.Storage Storage Description #1A 307.79' 1,406 cf 25.25'W x 60.58'L x 3.50'H Field A 5,353 cf Overall ‐ 1,838 cf Embedded = 3,516 cf  x 40.0% Voids #2A 308.29' 1,838 cf ADS_StormTech SC‐740 +Cap  x 40  Inside #1 Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 40 Chambers in 5 Rows #3 308.39' 24 cf 12.0"  Round Pipe Storage L= 30.0' 3,268 cf Total Available Storage      Storage Group A created with Chamber Wizard Device Routing     Invert Outlet Devices #1 Discarded 307.79'15.000 in/hr Exfiltration over Wetted area    Conductivity to Groundwater Elevation = 300.75'    #2 Secondary 310.63'6.0"  Round Culvert   L= 26.0'   CPP, projecting, no headwall,  Ke= 0.900    Inlet / Outlet Invert= 310.63' / 308.90'   S= 0.0665 '/'   Cc= 0.900    n= 0.013  Corrugated PE, smooth interior,  Flow Area= 0.20 sf    Discarded OutFlow  Max=0.99 cfs @ 12.13 hrs  HW=310.64'   (Free Discharge) 1=Exfiltration  ( Controls 0.99 cfs) Secondary OutFlow  Max=0.00 cfs @ 12.13 hrs  HW=310.64'   (Free Discharge) 2=Culvert  (Inlet Controls 0.00 cfs @ 0.27 fps) Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 41HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond 1P: Infiltration basin ‐ Chamber Wizard Field A Chamber Model = ADS_StormTech SC‐740 +Cap (ADS StormTech® SC‐740 with cap length) Effective Size= 44.6"W x 30.0"H => 6.45 sf x 7.12'L = 45.9 cf Overall Size= 51.0"W x 30.0"H x 7.56'L with 0.44' Overlap 51.0" Wide + 6.0" Spacing = 57.0" C‐C Row Spacing 8 Chambers/Row x 7.12' Long +0.81' Cap Length x 2 = 58.58' Row Length +12.0" End Stone x 2 = 60.58' Base Length 5 Rows x 51.0" Wide + 6.0" Spacing x 4 + 12.0" Side Stone x 2 = 25.25' Base Width 6.0" Stone Base + 30.0" Chamber Height + 6.0" Stone Cover = 3.50' Field Height 40 Chambers x 45.9 cf = 1,837.6 cf Chamber Storage 5,353.5 cf Field ‐ 1,837.6 cf Chambers = 3,515.9 cf Stone x 40.0% Voids = 1,406.3 cf Stone Storage Chamber Storage + Stone Storage = 3,243.9 cf = 0.074 af Overall Storage Efficiency = 60.6% Overall System Size = 60.58' x 25.25' x 3.50' 40 Chambers 198.3 cy Field 130.2 cy Stone Stewart's Shops‐South Broadway‐Postdevelopment Type II 24‐hr  100 yr Rainfall=6.24"South Broadway‐Post   Printed  1/12/2023Prepared by Stewart's Shops Page 42HydroCAD® 10.10‐7c  s/n 12543  © 2022 HydroCAD Software Solutions LLC Pond 1P: Infiltration basin Inflow Outflow Discarded Secondary Hydrograph Time (hours) 2423222120191817161514131211109876543210Flow (cfs)4 3 2 1 0 Inflow Area=0.494 ac Peak Elev=310.65' Storage=2,872 cf 4.28 cfs 0.99 cfs0.99 cfs 0.00 cfs Soil Map—Saratoga County, New York (South Broadway) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/12/2022 Page 1 of 34769600476961047696204769630476964047696504769660476961047696204769630476964047696504769660598610598620598630598640598650598660598670598680598690 598610 598620 598630 598640 598650 598660 598670 598680 598690 43° 4' 23'' N 73° 47' 19'' W43° 4' 23'' N73° 47' 15'' W43° 4' 21'' N 73° 47' 19'' W43° 4' 21'' N 73° 47' 15'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 0 20 40 80 120Feet 0 5 10 20 30Meters Map Scale: 1:432 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Saratoga County, New York Survey Area Data: Version 22, Sep 10, 2022 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Sep 9, 2020—Sep 16, 2020 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—Saratoga County, New York (South Broadway) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/12/2022 Page 2 of 3 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI WnA Windsor loamy sand, 0 to 3 percent slopes 0.6 100.0% Totals for Area of Interest 0.6 100.0% Soil Map—Saratoga County, New York South Broadway Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/12/2022 Page 3 of 3 Saratoga County, New York WnA—Windsor loamy sand, 0 to 3 percent slopes Map Unit Setting National map unit symbol: 2svkg Elevation: 0 to 990 feet Mean annual precipitation: 36 to 71 inches Mean annual air temperature: 39 to 55 degrees F Frost-free period: 140 to 240 days Farmland classification: Farmland of statewide importance Map Unit Composition Windsor, loamy sand, and similar soils:85 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Windsor, Loamy Sand Setting Landform:Outwash terraces, outwash plains, dunes, deltas Landform position (three-dimensional):Tread, riser Down-slope shape:Linear, convex Across-slope shape:Linear, convex Parent material:Loose sandy glaciofluvial deposits derived from granite and/or loose sandy glaciofluvial deposits derived from schist and/or loose sandy glaciofluvial deposits derived from gneiss Typical profile O - 0 to 1 inches: moderately decomposed plant material A - 1 to 3 inches: loamy sand Bw - 3 to 25 inches: loamy sand C - 25 to 65 inches: sand Properties and qualities Slope:0 to 3 percent Depth to restrictive feature:More than 80 inches Drainage class:Excessively drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to very high (1.42 to 99.90 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Maximum salinity:Nonsaline (0.0 to 1.9 mmhos/cm) Available water supply, 0 to 60 inches: Low (about 3.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2s Hydrologic Soil Group: A Map Unit Description: Windsor loamy sand, 0 to 3 percent slopes---Saratoga County, New York South Broadway Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/12/2022 Page 1 of 2 Ecological site: F144AY022MA - Dry Outwash Hydric soil rating: No Data Source Information Soil Survey Area: Saratoga County, New York Survey Area Data: Version 22, Sep 10, 2022 Map Unit Description: Windsor loamy sand, 0 to 3 percent slopes---Saratoga County, New York South Broadway Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/12/2022 Page 2 of 2 Extreme Precipitation Tables Northeast Regional Climate Center Data represents point estimates calculated from partial duration series. All precipitation amounts are displayed in inches. Smoothing Yes State New York Location Longitude 73.788 degrees West Latitude 43.073 degrees North Elevation 0 feet Date/Time Wed, 14 Dec 2022 14:23:14 -0500 Extreme Precipitation Estimates 5min 10min 15min 30min 60min 120min 1hr 2hr 3hr 6hr 12hr 24hr 48hr 1day 2day 4day 7day 10day 1yr 0.27 0.41 0.51 0.67 0.84 1.05 1yr 0.73 0.97 1.20 1.48 1.82 2.24 2.54 1yr 1.98 2.44 2.81 3.44 3.95 1yr 2yr 0.33 0.51 0.63 0.83 1.04 1.29 2yr 0.90 1.15 1.48 1.80 2.17 2.61 2.93 2yr 2.31 2.82 3.29 3.93 4.45 2yr 5yr 0.39 0.61 0.76 1.02 1.30 1.63 5yr 1.12 1.43 1.86 2.25 2.69 3.20 3.60 5yr 2.83 3.46 3.99 4.66 5.28 5yr 10yr 0.44 0.69 0.87 1.18 1.54 1.93 10yr 1.33 1.68 2.21 2.67 3.17 3.73 4.21 10yr 3.30 4.05 4.63 5.30 6.01 10yr 25yr 0.52 0.83 1.05 1.45 1.92 2.43 25yr 1.66 2.09 2.77 3.33 3.94 4.57 5.18 25yr 4.05 4.98 5.63 6.30 7.14 25yr 50yr 0.58 0.94 1.20 1.69 2.28 2.90 50yr 1.97 2.46 3.32 3.96 4.64 5.34 6.06 50yr 4.73 5.82 6.53 7.17 8.14 50yr 100yr 0.67 1.09 1.40 1.99 2.71 3.44 100yr 2.33 2.90 3.93 4.69 5.45 6.24 7.09 100yr 5.52 6.82 7.59 8.18 9.27 100yr 200yr 0.76 1.25 1.62 2.32 3.21 4.09 200yr 2.77 3.42 4.68 5.56 6.42 7.29 8.30 200yr 6.45 7.98 8.82 9.33 10.57 200yr 500yr 0.92 1.51 1.98 2.87 4.03 5.15 500yr 3.48 4.25 5.88 6.95 7.97 8.97 10.23 500yr 7.94 9.84 10.76 11.10 12.58 500yr Lower Confidence Limits 5min 10min 15min 30min 60min 120min 1hr 2hr 3hr 6hr 12hr 24hr 48hr 1day 2day 4day 7day 10day 1yr 0.22 0.34 0.42 0.56 0.69 0.82 1yr 0.60 0.80 0.94 1.23 1.59 1.93 2.30 1yr 1.71 2.21 2.41 3.00 3.44 1yr 2yr 0.31 0.48 0.59 0.80 0.98 1.15 2yr 0.85 1.12 1.28 1.65 2.06 2.53 2.84 2yr 2.24 2.73 3.19 3.81 4.34 2yr 5yr 0.36 0.56 0.69 0.95 1.21 1.34 5yr 1.04 1.31 1.51 1.93 2.45 2.96 3.34 5yr 2.62 3.21 3.72 4.34 4.95 5yr 10yr 0.40 0.62 0.76 1.07 1.38 1.52 10yr 1.19 1.49 1.71 2.16 2.74 3.33 3.77 10yr 2.95 3.62 4.17 4.78 5.46 10yr 5min 10min 15min 30min 60min 120min 1hr 2hr 3hr 6hr 12hr 24hr 48hr 1day 2day 4day 7day 10day 25yr 0.47 0.71 0.88 1.26 1.65 1.79 25yr 1.43 1.75 2.01 2.50 3.19 3.91 4.42 25yr 3.46 4.25 4.84 5.42 6.20 25yr 50yr 0.52 0.79 0.98 1.41 1.90 2.02 50yr 1.64 1.98 2.26 2.79 3.58 4.40 4.98 50yr 3.89 4.79 5.43 5.97 6.84 50yr 100yr 0.58 0.88 1.10 1.59 2.18 2.29 100yr 1.88 2.24 2.56 3.11 4.01 4.94 5.62 100yr 4.37 5.40 6.09 6.57 7.54 100yr 200yr 0.65 0.98 1.24 1.80 2.51 2.59 200yr 2.17 2.53 2.89 3.49 4.50 5.56 6.33 200yr 4.92 6.09 6.84 7.23 8.31 200yr 500yr 0.77 1.14 1.47 2.14 3.04 3.05 500yr 2.62 2.99 3.40 4.03 5.24 6.51 7.40 500yr 5.77 7.12 7.98 8.17 9.45 500yr Upper Confidence Limits 5min 10min 15min 30min 60min 120min 1hr 2hr 3hr 6hr 12hr 24hr 48hr 1day 2day 4day 7day 10day 1yr 0.30 0.46 0.56 0.76 0.93 1.08 1yr 0.80 1.06 1.21 1.55 1.98 2.41 2.77 1yr 2.14 2.67 3.05 3.74 4.23 1yr 2yr 0.35 0.53 0.66 0.89 1.10 1.23 2yr 0.95 1.20 1.37 1.76 2.25 2.71 3.05 2yr 2.39 2.93 3.40 4.06 4.60 2yr 5yr 0.42 0.65 0.80 1.10 1.40 1.59 5yr 1.21 1.55 1.77 2.24 2.77 3.44 3.89 5yr 3.05 3.74 4.28 4.99 5.64 5yr 10yr 0.50 0.77 0.95 1.33 1.72 1.94 10yr 1.48 1.90 2.16 2.69 3.27 4.15 4.70 10yr 3.67 4.52 5.12 5.86 6.60 10yr 25yr 0.64 0.97 1.20 1.72 2.26 2.52 25yr 1.95 2.47 2.90 3.46 4.11 5.31 6.04 25yr 4.70 5.81 6.49 7.26 8.13 25yr 50yr 0.76 1.15 1.43 2.06 2.77 3.08 50yr 2.39 3.01 3.41 4.18 4.88 6.40 7.30 50yr 5.66 7.02 7.77 8.56 9.54 50yr 100yr 0.91 1.37 1.71 2.48 3.40 3.76 100yr 2.93 3.68 4.16 5.05 5.81 7.71 8.84 100yr 6.83 8.50 9.32 10.08 11.19 100yr 200yr 1.09 1.63 2.07 3.00 4.18 4.60 200yr 3.61 4.50 5.06 6.13 6.91 9.32 10.72 200yr 8.25 10.30 11.17 11.85 13.12 200yr 500yr 1.39 2.06 2.65 3.85 5.48 6.01 500yr 4.73 5.88 6.59 7.89 8.73 11.98 13.84 500yr 10.60 13.30 14.19 14.75 16.23 500yr D. NYSDEC ENVIRONMENTAL MAP, FEMA MAP NYS OFFICE OF PARKS, RECREATION AND HISTORIC PRESERVATION (OPRHP) CORRESPONDENCE Wetland Map-Stewart's-S. BroadwaySources: Esri, HERE, Garmin, Intermap, increment P Corp., GEBCO,USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, OrdnanceSurvey, Esri Japan, METI, Esri China (Hong Kong), (c)OpenStreetMap contributors, and the GIS User CommunityJanuary 3, 202300.30.60.15mi00.510.25km1:18,056Not a legal documentNYS Department of Environmental Conservation KATHY HOCHUL Governor ERIK KULLESEID Commissioner January 06, 2023 Ryan Rubado Designer Stewart's Shops PO Box 435 Saratoga Springs, NY 12866 Re: DEC Stewart's Shop #495 - Saratoga Springs 177 S Broadway, Saratoga Springs, NY 12866 23PR00111 Dear Ryan Rubado: Thank you for requesting the comments of the Office of Parks, Recreation and Historic Preservation (OPRHP). We have reviewed the project in accordance with the New York State Historic Preservation Act of 1980 (Section 14.09 of the New York Parks, Recreation and Historic Preservation Law). These comments are those of the OPRHP and relate only to Historic/Cultural resources. They do not include potential environmental impacts to New York State Parkland that may be involved in or near your project. Such impacts must be considered as part of the environmental review of the project pursuant to the State Environmental Quality Review Act (New York Environmental Conservation Law Article 8) and its implementing regulations (6 NYCRR Part 617). Based upon this review, it is the opinion of OPRHP that no properties, including archaeological and/or historic resources, listed in or eligible for the New York State and National Registers of Historic Places will be impacted by this project. If further correspondence is required regarding this project, please be sure to refer to the OPRHP Project Review (PR) number noted above. Sincerely, R. Daniel Mackay Deputy Commissioner for Historic Preservation Division for Historic Preservation rev: J. Schreyer New York State Office of Parks, Recreation and Historic PreservationDivision for Historic Preservation, Peebles Island, PO Box 189, Waterford, New York 12188-0189(518) 237-8643 • https://parks.ny.gov/shpo E. CONSTRUCTION DRAWINGS F. SWPPP REVISIONS/UPDATES