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HomeMy WebLinkAboutConsultant Review - 154 MAIN STREET 10/21/2008 �t Land.Use Planning Civil Engineering C(„„, 1 S UPli n" �'I N x Construction Pernlltting October 21,2008 Mr. John Simons, Chairman Planning Board Town of North Andover 1600 Osgood Street North Andover,MA 01845 Via hand delivery RE: Engincering Review—Bank of America- 154 Main Street North Andover,MA Dear Chairman Simons: The purpose of this correspondence is to respond to the Engineer review comments for the above referenced project,as submitted to your Board on 10/17/08 by VHB. The following response and brief description of each comment is offered for your review: I REM I 1: Town of North Andover Zoning Bylaw 1.) The plans indicate that a landscape area is proposed.... Attached please find a revised plan set with a Landscape Plan included. General Comments 2.) The plan shows new paving in the widened driveway. The pavement location.... All existing bituminous concrete to be removed,the proposed parking lot will be entirely new pavement. A note has been added to the plan to indicate this. 3.) The plan shows closing one of the driveway curb cuts with vertical granite curbing. The required saw- cutting of'pavement and curbing should be shown.... The site plan has been revised with a saw-cut line and a note requiring the resetting of the existing'brick walkway. 4.)A detail of'the crushed stone throat connection... The plan has been revised to require a bituminous concrete throat. 5.) The curbing for the widened entrance appears to be located directly over a utility pole... Tel: 781-659-8187 () Fax: 781-659-81.86 o 687 Main Street <., PO Box 5175 Norwell, MA 02061 �� Proposed Parking Improvements 154 Main Street—North Andover,MA Response to Engineer Review Comments October 21,2008 Page 2 of 4 The curb layout has been revised to avoid any conflict with the existing utility pole. 6.) The plans should provide a sidewalk detail. We have incorporated the sidewalk detail as part of the curb detail. 7.) The type of curbing proposed and extents of the curbing..... The Site Plan has been revised to state the type of curbing and the extent of the proposed curbing. 8.) A detail for the proposed accessible curb ramp should be provided..... The layout for the proposed handicapped access has been revised to comply with ADA standards. 9.) The limits of the retaining wall to be added to the plan. The limits of the retaining wall have been added to the plan. 10.)A detail of the pipe penetration through the retaining wall should be provided. Refer to the additional Detail Sheet for the required detail. 11.)A detail of the retaining wall and guardrail should be added to the plans. The detail should include a cross section.... A detail of the retaining wall has been added to the site plan,per the request of the Conservation Commission,the applicant is proposing a three foot reveal to the proposed retaining wall in lieu of a guardrail. 12.) The pipe connection to the Stormfilter is shown on the plan at a sharp angle The pipe connection at the Stormfilter shall be secured at the structure. 13.)A label and a detail of the rip rap apron should be added to the plans. The details should include length, width, stone size.... Please refer to the detail sheet for a detail of the rip rap apron. 14.) The invert out of the subsurface infiltration bed should be added to the plans. We have added the invert out of the subsurface infiltration bed to the Site Plan. 15.) The material of the outlet control structure baffle should be provided and method of connecting... We have revised the outlet control structure detail. 16) The outlet control structure should have been detailed with a similar amount of detail as.... We have revised the outlet control structure detail. Proposed Parking Improvements 154 Main Street—North Andover, MA Response to Engineer Review Comments October 21,2008 Page 3 of 4 17.) The inlet pipe shown on the detail "Section View of Storm Filter Connection to Recharge Chambers" from the Storrnfilter.... The Pipe layout has been revised accordingly. 18.)A detail of the subsurface infiltration bed should be added to the plan. The detail has been added to the inspection port. 19.) The Stormfilter unit and Recharger units vary in height. The details and cross sections do not reflect a difference in height. The details should be revised... The detail has been revised with the required elevations. 20.) The proposed location of the relocated BOA sign is not provided. The Site Plan has been revised to show the proposed relocation. Drainage Comments 15.) The Control point in the drainage calculations summary page... The summary page has been revised accordingly. 16) The peak discharge rates should be provided in the summary for both control points(Main Street and Osgood Pond) The summary page has been revised accordingly. 17.) The High Groundwater elevation in the area of the infiltration bed has not been provided... We have estimated the seasonal high groundwater based on two different of observations of the site. The elevation of Osgood Pond is approximately twenty five feet below the elevation of the existing parking lot. The National Resources Conservation Service Soil Survey for the locus estimates that the soil on site consists of a Canton fine sandy loam indicating that water is greater than six feet below the surface. 18.) The discharge location for the existing catch basin in the driveway to be closed is not provided. The discharge location of the existing catch basin is not known. Because it is located within the Town layout,we assume it connects to the Town Drainage System. 19.) The applicant has submitted drainage calculations which support the design... We concur. Proposed Parking Improvements 154 Main Street—North Andover, MA Response to Engineer Review Comments October 21,2008 Page 4 of 4 This concludes our response to the comments submitted to the Planning Board on 10/17/08. We appreciate the thoughtful input from this review process, and look forward to reviewing this material with the Planning Board at our next scheduled hearing 10/21/08. If you have any questions regarding this material,please contact me anytime at my office at 781-659-8187. i , Sincerely, r 11 r /6AVANARO�CONSUI4�ING, INC. ;f John C.Cavanaro,P.E. -._—' Principal Enclosure Cc: -Judy"Tymon,North Andover Town Planner Jennifer A. Hughes,North Andover Conservation Administrator T. Daigle File 8062 SECTION Vlll DRAINAGE CALCULATIONS & SUPPLEMENTAL DRAINAGE INFORMATION 1.0 METHODOLOGY The adequacy of the proposed drainage structures and their ability to function properly were analyzed to minimize detrimental effects due to storm water conditions.The impacts of storm water are mitigated through several mechanisms such as infiltration,transportation and evaporation.The remaining runoff,was quantified through developed and accepted methods.By determining the characteristics of site specific storm water conditions, mitigating efforts have be taken to avoid floodwater damage by constructing control devices. Design and analysis of these facilities included the evaluation of site data through observations,computer modeling the watershed, and the interpretation and application of the calculated values. 2.0 OVERVIEW Cavanaro Consulting,Inc. (CC)has analyzed the existing conditions at the site utilizing the HydroCad Storm water modeling program. Storm rainfall,run-off curve numbers,and other site characteristics are input into the program. The results of calculations are output into tables and graphs for each area and control structure. The complete calculations are presented in Attachment A of this Report. 3.0 DESIGN STORMS CC has computed storm water run-off calculations for the proposed site,for a 2, 10 and 100 year,24-hour storm events. This results in a 3.1",4.5"and a 6.4"rain for each storm event. 4.0 DRAINAGE AREAS The existing site consists of two drainage areas,one area that flows to the rear of the property and a smaller drainage area that flows to Main Street.The proposed site will have two subcatchment areas;the majority of the existing lot will be routed through the proposed Deep Sump Catch Basin, Cultec Stormfilter and Recharge chambers with an overflow at the rear of the property to a swale. The remainder of the lot will discharge towards the street as it does today. 5.0 DRAINAGE ANALYSIS Design Control Point(2R) Storm Existing Conditions(ECP) Post-development(PCP) 2—Year-24Hour(3.10") 0.49 cfs 0.45 cfs 10—Year-24Hour(4.50") 1.00 cfs 0.96 cfs 100—Year-24Hour(6.40") 1.76 cfs 1.52 cfs Design Control Point(4R) Storm Existing Conditions(ECP) Post-development(PCP) 2—Year-24Hour(3.10") 0.12 cfs 0.11 cfs 10—Year-24Hour(4.50") 0.18fs 0.17 cfs 100---Year-24Hour(6.40") 0.26 cfs 0.26 cfs As seen on the above calculations the proposed drainage improvements will result in no change or a decrease in runoff in all of the storms modeled. The calculations represent a decrease in runoff in the two through one hundred year storms to Design Control Point 2R. The proposed work results in a significant storage,structural and treatment improvements to the existing drainage conditions. C1 ' Land Use Plann CAVANARO CONSUL'T'ING Civil Engineer Construction Permitt November 10,2008 Mr.John Simons, Chairman Planning Board Town of North Andover 1600 Osgood Street North Andover,MA 01845 Via hand delivery RE: Engineering Review—Bank of America-154 Main Street North Andover,MA Dear Chairman Simons: The purpose of this correspondence is to respond to the Engineer review comments for the above referenced project,as submitted to your Board on 10/17/08 by VHB. The following response and brief description of each comment is offered for your review: Win 07 ff Frx.VIM Q MQMM 1=,M pTm 0 1 I: Town of North Andover Zoning Bylaw / The plans indicate that a landscape area is proposed.... Attached please find a revised plan set with a Landscape Plan included. .General Comments 2.) The plan shows new paving in the widened driveway. The pavement location.... All existing bituminous concrete to be removed,the proposed parking lot will be entirely new pavement. A note has been added to the plan to indicate this. 3.) The plan shows closing one of the driveway curb cuts with vertical granite curbing. The required saw- 1 / utting of pavement and curbing should be shown.... V The site plan has been revised with a saw-cut line and a note requiring the resetting of the existing brick walkway. It)A detail of the crushed stone throat connection... \i The plan has been revised to require a bituminous concrete throat. 5.) The curbing for the widened entrance appears to be located directly over a utility pole... Proposed Parking Improvements 154 Main Street—North Andover,MA Response to Engineer Review Comments November 10,2008 Page 2 of 4 The curb layout has been revised to avoid any conflict with the existing utility pole. 6) The plans should provide a sidewalk detail. "We have incorporated the sidewalk detail as part of the curb detail. Z:) The type of curbing proposed and extents of the curbing..... The Site Plan has been revised to state the type of curbing and the extent of the proposed curbing. b)f A detail for the proposed accessible curb ramp should be provided..... r The layout for the proposed handicapped access has been revised to comply with ADA standards. 9.) The limits of the retaining wall to be added to the plan. The limits of the retaining wall have been added to the plan. 10.)A detail of the pipe penetration through the retaining wall should be provided. V,. Refer to the additional Detail Sheet for the required detail. /,)A detail of the retaining wall and guardrail should be added to the plans. The detail should include a 1cross section.... A detail of the retaining wall has been added to the site plan,per the request of the Conservation Commission,the applicant is proposing a three foot reveal to the proposed retaining wall in lieu of a guardrail. 12.) The pipe connection to the Stormfilter is shown on the plan at a sharp angle The pipe connection at the Stormfilter shall be secured at the structure. �13.)A label and a detail of the rip rap apron should be added to the plans. The details should include /i length, width, stone size.... J Please refer to the detail sheet for a detail of the rip rap apron. 1 The invert out of the subsurface infiltration bed should be added to the plans. We have added the invert out of the subsurface infiltration bed to the Site Plan. The material of the outlet control structure baffle should be provided and method of connecting... r' l f We have revised the outlet control structure detail. 16) The outlet control structure should have been detailed with a similar amount of detail as.... We have revised the outlet control structure detail. Proposed Parking Improvements 154 Main Street—North Andover,MA Response to Engineer Review Comments November 10,2008 Page 3 of 4 17.)The inlet pipe shown on the detail "Section View of Storm Filter Connection to Recharge Chambers" from the Stormfilter.... i . The Pipe layout has been revised accordingly. f~ 18.),4 detail of the subsurface infiltration bed should be added to the plan. i The,detail has been added to the inspection port. i 19.)The Stormfilter unit and Recharger units vary in height. The details and cross sections do not reflect a difference in height. The details should be revised... The detail has been revised with the required elevations. 20.) The proposed location of the relocated BOA sign is not provided. l The Site Plan has been revised to show the proposed relocation. Drainage Comments 15.) The Control point in the drainage calculations summary page.., The summary page has been revised accordingly. 16)The peak discharge rates should be provided in the summary for both control points(Main Street and Osgood Pond) The summary page has been revised accordingly. 1he17.) The High Groundwater elevation in the area of the infiltration bed has not been provided... e estimated the seasonal hi h oundwate g �" r based on two different of observations of the site. The n of Osgood Pond is approximately twenty five feet below the elevation of the existing parking lot. tional Resources Conservation Service Soil Survey for the locus estimates that the soil on site of a Canton fine sandy loam indicating that water is greater than six feet below the surface. In to these factors,the applicant is willing to provide exploratory test pits to confirm the location of l high groundwater prior to construction as a condition of approval.e discharge location for the existing catch basin in the driveway to be closed is not provided.c arge location of the existing catch basin is not known. Because it is located within the Town layout,we assume it connects to the Town Drainage System. 19.) The applicant has submitted drainage calculations which support the design... We concur. Proposed Parking Improvements 154 Main Street—North Andover,MA Response to Engineer Review Comments November 10,2008 Page 4 of 4 This concludes our response to the comments submitted to the Planning Board on 10/17/08. We appreciate the thoughtful input from this review process,and look forward to reviewing this material with the Planning Board at our next scheduled hearing 11/18/08. If you have any questions regarding this material,please contact me anytime at my office at 781-659-8187. S' ely, CAVAN RO CONS TING, INC. John C. Ca n ,P. Principal Enclosure Cc: Judy Tymon,North Andover Town Planner Jennifer A.Hughes,North Andover Conservation Administrator T.Daigle File 8062