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20190467 Station Lane Apts Engineering Response 8-14-19 2452 STATE ROUTE!9 (4 -. LAnkNpirialo ENGINEERING, PC MALTA,NYI'12 TE 20 T(51 BJ 999-5243 F[5113)1399-5245 August 14, 2019 Mr. Mark Torpey, Chairman Planning Board City of Saratoga Springs 474 Broadway Saratoga Springs,NY 12866 RE: Station Lane Apartments(Askew) City Project No. 17.062/20190467 Dear Mr. Torpey: Lansing Engineering has reviewed the June 24, 2019 comment letter prepared by Bradley Grant, Barton& Loguidice, D.P.C.,regarding the above noted project. The following summarizes the comments followed by our responses. General Existing utilities are close by and able to be connected to. Confirm conditions at existing manhole, bench and steps to verify not in conflict with new incoming pipe from project. Response: Comment noted. The sanitary laterals are proposed to be connected to the sanitary main via a tapping saddle and typical wye connection as noted in detail 4 on Sheet DT-3 under Existing Sanitary Main therefore inspection and modifications of existing manholes will not be required. 1. Comment: We note change in residential units proposed from 27 at November 1, 2018 planning Board meeting minutes to 29 units consisting of a twelve-unit building, an l lunit building and a 6-unit building. All units would be 3 story; Response:As noted in item#4 of the Planning Board's Notice of Decision from the January 10, 2019 meeting granting the issuance of a Special Use Permit, the approval granted was for up to 29 multi family residential units. 2. Comment: Please submit copy of NYSDEC wetland permit; Response: DEC Permit#5-4115-00237/00001 (FW, WQJ, dated May 25, 2017 was issued for the original site plan. Permit Modification #1 dated June 11, 2019 was issued and is attached. 3. Comment: It remains to be determined what mitigation will be required for the existing sewage pump station adjacent to the project on Station Lane.Needs include provision of a generator and other improvements related to ability to reliably serve this project and others proposed nearby that would be tributary to this station; Response:An email was distributed by Doug Heller of the LA Group dated May 28, 2019 outlining the total project costs and projected cost sharing for upgrades to the existing pump station to accommodate the Faders,Intrada and Askew development projects. The total costs including contractor bid and engineering fees was identified as$151,278. Using a cost-sharing formula Station Lane Apartments August 14, 2019 2 of 8 based on projected design flows, the Askew Station Lane project's fair-share contribution for the pump station upgrades was identified as$23,740. As noted previously, the applicant has committed to making his fair-share contribution to the upgrades. The Vecino Group, developers of the Intrada Saratoga project have committed to undertake the construction of the improvements. 4. Comment: There was a comment regarding the under-developed proposed Civic space in the middle of the project. Walks, sculpture and 2 park benches are proposed. Confirm City stance on newly proposed features; Response: We have discussed some ideas with Lindsey Connors, Community Development Planner with the City's Office of Planning and Economic Development who is the staff support for the Arts Commission. In light of projected site construction costs that are significantly higher than originally expected, the budget for the art feature is very limited at this time. We are working with the owner and the architect on a plan that we can bring before the Arts Commission for review. 5. Comment: Confirm trucks can maneuver on proposed paved road. Show Garbage truck movements on plan that confirm ability to turn around without needing a parking space that may not be available.; Response: The site driveway and parking lot were designed to accommodate garbage trucks. Sheet VP-1 has been added to illustrate the entering and 'xiti g, turning movements of a garbage truck. 6. Comment: Are buildings slab on grade with no basement or crawl spaces? Response: The proposed buildings are slab on grade with no basements. Water and Sanitary Sewer I. Comment: We request confirmation that the new fire sprinkler systems can get the required fire flow from the system per NFPA standards. Discuss internal plumbing connections to existing building briefly and show fire flow computations in Engineer's Report. Hydrant flow tests are included in the report that indicate over 1600 GPM at West Avenue/Church intersection but no elevation is given at that location. The calculations show a fire demand of 1 500 GPM for the 1,800 SF fire-flow calculation area. Please elaborate what zone, presumably in each building,this pertains to. Can the required fire flow demand be furnished through 4-inch water services,pressure reduction by backflow preventer and accounting for all pressure losses?Please add a brief section to the report discussing service sizing, pressure losses and available pressure and capacity at third floor sprinkler heads. Response: The waterline at the intersection of West Avenue and Church Street is at approximate elevation of 345'and the proposed first floor grade elevations at the project site range from 325.95' to 329.25'. Due to the revised building footprints,the 1,800 SF apartment area has been reduced to 1,110 SF. This area corresponds with the total floor area of one apartment unit on each floor. The water service sizing cannot be completed until the architect and MEP engineer complete the interior building design and plumbing design for the buildings. The service is estimated at a 4" DIP however is subject to change due calculations to determine actual fire flow required based on final interior floor areas and sprinkler system specifications. The correct sizing will be determined and provided once received. 2. Comment: Where will a RPZ backflow preventer be located for this project, inside each building? Factor in RPZ and all head losses for fire prevention calculations. Response: The location of the RPZ is unknown and shall be determined by the architect and MEP engineer and the fire prevention calculations shall take into account the head losses and the RPZ for calculation purposes. Station Lane Apartments August 14, 2019 3 of 8 3. Comment: How many land 2 bedroom units are proposed?2.5 residents per unit are used for the demand calculations and sewer flow generation values. Open existing sanitary sewer manhole and assess need to move internal steps if in close proximity to new pipe from the project; Response: The current proposal is for(26) 2-bedroom units and(3) 1-bedroom units. 2.5 residents per unit is a typical per unit demand for 2-bedroom units.As a conservative measure the 2.5 residents per unit were also utilized for the 1-bedroom apartments. The sanitary laterals are proposed to be connected to the sanitary main via a tapping saddle and typical wye connection as noted in detail 4 on Sheet DT-3 under Existing Sanitary Main therefore inspection and modifications of existing manholes will not be required. 4. Comment: How will existing wastewater be conveyed/stored when the three sewer laterals are connected to the existing system?Provide notes on the plans that accommodate existing sewer flows and continuance of service for the train station and other users. Response: The wastewater service connections will consist of a typical live tap utilizing a tapping saddle as approved by the Department of Public Works and wye connection as noted in detail 4 on Sheet DT-3 under Existing Sewer Main. This connection type will allow the main to continue in service throughout the entire service connection process. Stormwater Stormwater Pollution Prevention Plan (SWPPP) 1. Comment: Please provide a soil map that delineates the extent of the Deerfield and Wareham soils. Is there any appreciable portion of the site outside of wetlands where infiltration is possible in the Deerfield Loamy Fine Sand?If of significant size it could impact the value of S for RRv calculation. Response:Sheet EC-1 of the SWPPP has been revised to include the soil boundaries. The parcel contains all Deerfield and Wareham soils however during site investigation extremely high groundwater was found.Due to the high groundwater and water laying along the surface, lack of infiltration iJtrrrliun of the groundwater, and amount of wetlands on the site, the soils on site have the characteristics of D type soils and have been modeled as such. 2. Comment: Add a brief section that describes the ability of the existing culvert size, condition and ability to receive site drainage and not increase drainage concerns downstream. Response:As-bunts drawings of Station Lane were obtained from the City of Saratoga Springs and include call outs noting a 30"RCP culvert runs under Station Lane. Section 6.3 of the SWPPP provides a comparison table of the Design Point 1 (the existing culvert) and demonstrates the post- development runoff rates are less than the pre-development runoff rates. Therefore, the existing culvert will receive less stormwater than current conditions. 3. Comment: What green infrastructure practices are proposed? Storage and treatment seem to come via commercial non-green practices. Response: The green infrastructure practices proposed for the project are Conservation of Natural Areas and Tree Plantings/Tree Pits for the proposed street trees along Station Lane. The proposed green infrastructure practices meet and exceed the minimum required Runoff Reduction. See Appendix D of the SWPPP for the Green Infrastructure Calculations. Station Lane Apartments August 14, 2019 4 of 8 4. Comment: Provide calculations matching the treatment system capacities versus peak flow rate to the proposed units to ensure adequate capacity that considers this peak rate. It is our experience that a 1.15-inch storm in Hydrocad does not match the water quality volume. Typically increasing the 90% storm to around 1.7 -inches results in a similar volume to WQv and its real peak inflow rate the units must have capacity for. What is the individual capacities for each treatment unit and its associated factor of safety in treating the peak inflow associated with the WQv event? Response:As stated in Section 6.3 of the SWPPP, the Jellyfish filter orifice has been sized to treat up to and including the 1-year storm event of approximately 2.24 inches which is greater than the 1.15 inch storm required by the New York State Stormwater Design Manual. Included within Appendix D of the SWPPP is the CDS Unit Sizing worksheet which demonstrates the treatment capacity of the CDS Unit is 0.93 cfs and the peak discharge is 0.628 cfs which is less than the treatment capacity.Additionally, Sheets DT-6 and DT-7 of the plan set include details of the proposed Jellyfish units along with the treatment capacities and proposed flow rates of the 1-year storm event. Jellyfish] has a treatment capacity of 0.23 cfs and a proposed flow rate of 0.15 cfs from the 1-year storm. Jellyfish2 has a treatment capacity of 0.23 cfs and a proposed flow rate of 0.22 cfs from the 1-year storm event. 5. Comment: The Station Lane drainage piping proposed is noted to be a flat slope over almost 400'with 4' deep sumps. This is also noted to be turned over to the City for ownership and maintenance. This is an area of concern as discussed earlier. Response:Due to the various site constraints including the existing Station Lane being flat and limited elevation changes on site, the desired pipe slopes and pipe cover is unachievable.As a result, the drainage piping within stormwater management system#2 is proposed at a 0%slope. Per Section 6.4.3 of the New York State Stormwater Design Manual,pretreatment of stormwater can be calculated using the Camp-Hazen equation in order to determine the minimum square feet of required sedimentation basin. Sizing calculations are included within Appendix D of the SWPPP and demonstrate (2) 4'x4'inside diameter structures with 4'deep sumps are required for pretreatment. The site plans propose(3) deep sump catch basins for pretreatment. The stormwater management system was discussed at a meeting on May 1, 2019 between Matt Zeno,Albert Flick, and members of Lansing Engineering and determined to be adequate given the existing site conditions and constraints. Sheet 1 of 17-Cover Sheet 1. Comment: Please clarify the meaning and intent of note 7 under accessible route notes regarding 36-inch clear width. Response: The intent of note 7 is to reference ADA Standards,Section 4.3.3 Width— "The minimum clear width of an accessible route shall be 36 in (915 mm) except at doors."The intent is Haat note 7 is to reflect that minimum requirement. Notes 8, 9 and 10 should also be considered in conjunction with note 7 as they reflect the additional considerations outlined in the standards. Sheet 2 of 17 -Survey 1. Comment: The northerly end of the site has a finger of access to McGee Road and two storm sewers are at least partially shown. Where do these pipes start and end and are they conveying the source of stormwater to the culvert on Harbor Lane just east of the project? Label sizes of all pipes; Station Lane Apartments August 14, 2019 5 of 8 Response: The road runoff from a portion of NYS Route 9N drains to a low point in the southern edge of the NYS right-of-way,just north of the McGee Road permanent easement. The culverts pick up this low point and convey drainage into the wetland to the south on the subject parcel. The westerly culvert is a 30-inch CMP which is the outlet from an existing catch basin in the NYS ROW The easterly culvert appears to have been installed to allow McGee Road to cross an existing swale. The 30-inch CMP is labeled on the plan. That portion of the NYSDEC wetland drains to the south to the existing 36-inch RCP that crosses Station Lane at the parcels southeast corner. The pipe size of the 36-inch RCP crossing Station Lane has been added to the plan. 2. Comment: Label size of existing Station Lane storm culvert that will receive runoff from project. Response: The 36-inch RCP is now labeled on the survey. Sheet 3 of 17 Existing Conditions & Demolition Plan 1. Comment: Label existing water main size in Station Lane; Response: Based upon an as-built drawing received from the City of Saratoga Springs DPW, the 6"waterline has been labeled on Sheet ED-1. 2. Comment: Label all existing culvert sizes, see above; Response: The 36-inch RCP is now labeled on Sheet ED-1. 3. Comment: In the southeast corner of the site there appears to be a wetland upstream of the Station Lane Culvert. Is this a state or federal wetland?Please label accordingly. Response: All wetlands on-site have been delineated as NYSDEC jurisdictional wetlands. Additional labels have been added to the plans to clarify this statement. Sheet 4 of 17-Layout and Materials Plan Comment: The proposed guiderail along Station Lane proposed sidewalk is on the ditch side and offers no pedestrian protection from vehicular traffic. The south side of the road has a curb and thus protected. Can the guiderail go between the edge of the road and the sidewalk? Response: The sidewalk has been revised to include a curb for pedestrian protection. The proposed guiderail has remained on the ditch side of the sidewalk for pedestrian protection from the slope on the ditch side of the sidewalk. Sheet 5 of 17-Utilities and Plan 1. Comment: Label all roof leaders and indicate size; Response:At the request of the applicant, roof leaders have been removed where stormwater would flow off the rooftop and to a stormwater drainage structure resulting in roof leaders remaining on the back half of the middle building and rightmost building. The roof leaders remaining have been labeled as 6"in size and a note#2 on Sheet UG-1 indicates roof leaders shall be 6"SDR 35. 2. Comment: The proposed storm drainage piping at the proposed bump-out for on-street parking is approximately 400' long of 18-inch pipe at a 0.00% (flat)grade. This will likely result in sediment build-up of this likely oversized pipe and undue maintenance needs over its life. It appears the constraint is the presence of wetlands and the 100' buffer zone but can likely be overcome by conveying it farther at a positive grade Station Lane Apartments August 14, 2019 6of8 towards the existing culvert, perhaps to the south side or in the buffer zone on the north side.$'deep sumps are noted but concern is within pipelines and lack of cleansing velocity to transport sediments. Please clarify workable options. Response: Due to the various site constraints including the existing Station Lane being flat, limited elevation changes on site, and the presence of relatively high groundwater, the desired pipe slopes and pipe cover is unachievable.As a result, the drainage piping within stormwater management system#2 is proposed at a 0%slope. In the event the stormwater conveyance piping needs to be cleaned of sediment, the process is the same in that of typical sump cleaning of catch basins and can be applied as such. 3. Comment: Where does retaining wall at 11-unit building end at its southerly end. Is it along part of the foundation wall? Response: The retaining wall continues as part of the foundation wall and ends near the midpoint of the eastern most wall of the building. The callout on Sheet UG-1 at the end of the wall has been modified to specify the termination of the retaining wall. 4. Comment: Show elevations of sanitary sewer laterals at buildings that provide adequate cover. Response: Callouts have been added at the sanitary sewer connection locations and building locations to clearly indicate the invert of the sanitary sewer main and minimum invert elevation out of the building to illustrate there is adequate cover of the sanitary sewer laterals. Sheet 7 of 17- Erosion& Sediment Control Plan 1. Comment: Fully encircle sediment trap area and soil stockpile north of 6-unit building. Response: The silt fence has been modified to fully encircle the sediment trap and soil stockpile area. The typical soil stockpile will be surrounded by silt fence in its entirety.Additionally detail 3 on Sheet DT-1 specifies silt fencing shall be installed surrounding the soil stockpile areas. Sheet 8 of 17-Landscaping Plan 1. Comment: Suggest additional groundcover or low plantings for parking islands with parking island tree and one where nothing is shown to add color,texture and interest. If fully mulched these difficult to mow areas could be reduced. Response:Sheet LS-1 has been revised to include an additional tree within previously empty parking lot island. The sheet has also been revised to specify a ground cover in the parking lot islands consisting of mulch. 2. Comment: Suggest additional groundcover or low plantings at civic area and west end of 11 unit building. Response: The ground cover within the civic space area shall consist of grass/lawn areas. Sheet 9 of 17-Lighting Plan 1. Comment: Show grounding rod on streetlight detail. Response: The detail included on Sheet LT-1 is the City of Saratoga Springs Standard Decorative Light Detail and includes the ground rod. 2. Comment: Suggest moving rear wall building mounted light east towards door or provide another light near door. Station Lane Apartments August 14, 2019 7of8 Response:An additional building mounted light has been added to the rear of the central building to provide lighting near the rear entrance door. 3. Comment: Suggest a light in the rear of 6-unit building. Response:A building mounted light has been added to the rear of the 6-unit building. Sheet 14 of 17-Misc. Site Details (2 of 2) 1. Comment: Is rough sawn cedar siding for dumpster enclosure amenable to City of Saratoga Springs. Response:Rough sawn cedar siding has been proposed on several projects completed in the City of Saratoga Springs and has been approved as such. 2. Comment: Metal Beam guideraiI is shown near edge of pavement but without sidewalk, see previous comments on guiderail protection of pedestrians. Response: The sidewalk along Station Lane has been revised to include a 6"high concrete curb to provide pedestrian protection. The detail has been revised to include a sidewalk in front of the guiderail as proposed on the revised site plan. 3. Comment: Will there be underdrain(s)for the retaining wall?If so, show route and inverts on the plans. Response:Prior to construction the retaining walls shall be designed by a licensed geotechnical engineer and it will be determined if underdrains are required at that time.Additionally, the underdrain if required will be designed by the geotechnical engineer. Sheet 15 and 16 of 17-Stormwater Management Basin Details 1. Comment: Label all materials and depths of fill materials under, alongside and over stormwater chambers. Response:Detail 2, note 4 on Sheet DT-6 specifies the required stone and dimensions of stone required surrounding the system. The note states bedding material shall consist of 3/"to 2"clean crushed stone and the profile view included within the detail provides dimensions of all materials surrounding the stormwater chambers. Detail 2 on Sheet DT-7 includes a callout specifying 3/" clean crushed stone shall be installed for module bedding and the profile view included within the detail provides dimensions of all materials surrounding the stormwater modules. 2. Comment: It seems the entire chamber is enveloped in an impermeable liner. We assume the term infiltration in the detail referring to "surrounding the subsurface infiltration system is a term not associated with its design intent for this project. Please clarify; Response: The terminology has been revised to remove infiltration system and include stormwater management system. 3. Comment: Provide sub-base depth and material notes for foundation for treatment units; Response: The Jellyfish Filter Details have been revised to specify 6"of#1 crushed stone shall be installed for foundation of the treatment units. 4. Comment: Provide notes, dimensions and materials of construction for anti-seep collar on the detail. Response:A detail including material,size, and notes for manufactured anti-seep collars has been added to Sheet DT-6. Station Lane Apartments August 14, 2019 8 of 8 Attached please find a copy of the revised plan set for your review. If additional information is required,please contact our office at your earliest convenience. Thank you. Sincerely, LAJ1N 7piEN,INEERING, PC , iit-'4 y - _____,...-. Mid f ac l r,a i c h i n , Senior Engineer CC: Richard Askew(Applicant)