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HomeMy WebLinkAboutRea's Pond 150410 Request for Wavier WSP COMMITMENT &INTEGRITY 980 Washington Street I Suite 325 T 800.446.5518 DRIVE RESULTS Dedham, Massachusetts 02026 T 781.251.0200 www.woodardcurran.com F 781.251.0847 Via Electronic Mail April 10,2015 A* Jean Enright, Interim Planner 4msk Town of North Andover, Planning Department 1600 Osgood Street, Suite 2035 WOODARD North Andover, MA 01845 &CURRAN Re: Application for a Waiver of Watershed Protection District Special Permit Rea's Pond Pump Station Dear Ms. Enright: On behalf of the Town of North Andover Division of Public Works (DPW) Director, and pursuant to North Andover Zoning Bylaw,Woodard&Curran requests a waiver of the provisions of Section 4.136— Watershed Protection District Special Permit for the purpose of reconstruction of the Rea's Pond Wastewater Pump Station. The Project entails the relocation of the existing wastewater pump station outside of the 50' No-Build Zone, as well as outside of the FEMA Floodplain. The new station will replace the existing station, which is currently located in both the 50' No-Build Zone and the FEMA Floodplain, which pose an environmental risk, specifically to the public drinking water supply in Lake Cochichewick. The new station is designed to support the seasonal high and low flow variations with improved pumping capacity and wastewater storage, and enhance redundancy and resilience with an updated electrical service, backup controls and standby power. The need for the new pump station is both environmental and technical in nature. We are including a letter from the Department of Public Works Director Bruce Thibodeau to the North Andover Conservation Commission dated March 27, 2015 that outlines both the environmental and technical aspects as they relate to the water resources in the area. As it exists now, the Rea's Pond Wastewater Pump Station poses a potential threat to the public drinking water supply in the Lake. This waiver request for a Watershed Protection District Special Permit directly relates to the vital importance of the preservation and protection of the water resources in this location. Construction of the new, upgraded wastewater pumping station includes all site work, appurtenant utilities and services within the Town Right of Way (Great Pond Road) and on Town easements. A small access driveway will be installed for Town vehicles to access the station for daily maintenance. A Stormwater BMP is included to provide control and treatment of storm water runoff, as per the Massachusetts Stormwater Management Standards and the Town of North Andover Bylaw Standards. The new pump station site will be secured with a perimeter fence. Upon completion of the new station, the existing pump station will be demolished with the existing footprint and the existing gravel area reconfigured to provide parking for those using the area for recreation purposes. This reconfigured parking area was designed at the request of and in concert with the Conservation Commission. There have been multiple technical improvements to the station over the years, but despite these improvements, there is still a potential for a failure of the pump station during flood conditions. Under these conditions, operators cannot access the station and that is likely to result in a sanitary sewer overflow (SSO) and subsequently, spillage of wastewater into Lake Cochichewick, the Town's drinking water supply. With the technical and environmental issues aside,the typical service life for a pump station is about 20 years and Rea's Pond Pump Station is now beyond its lifespan. The proposed pump station is located within the Non-Disturbance Buffer Zone on a lot created before October 24, 1994. While it is understood that the wastewater pumping station is an allowed use within the Watershed Protection District By-Law, Section 4.136, specifically at Uses and Building Requirements, Section 3 (i)(2)(3), there are activities of the project further described in the By-Law at Section 4.136 (3)(c)(ii) as detailed below that we want further clarification of and are the subject of this waiver request. OODA (1) Any activities, which cause a change in topography or grade. — It is anticipated that changes in the &CURRAN grade of the site will be minimal. (2) Vegetation removal or cutting—the project will require removal of trees and vegetation within the work zone and the footprint of the proposed wastewater pumping station. It is anticipated that up to 4,100 square feet of wooded area will be cut and removed. All area other than the proposed driveway and structures will be replaced with grass. (4) Replacement of a permanent structure— The project does not contain a physical building, but pump station equipment with the majority below ground. The proposed project will replace the two existing wet wells, dry well,stand-by generator, and electrical and control panels with a new wet well, dry well, standby generator and electrical and control panels. The existing above ground propane tank will be removed. The proposed project will also include a pad-mounted transformer with containment area. The total number of structures on site will remain the same. (5) Any surface or sub-surface discharge,including but not limited to, storm water runoff;-The proposed project will include a Stormwater Best Management Practice(BMP)to treat and detain storm water runoff from the proposed access driveway as required by the Massachusetts Stormwater Management Standards,as well as the North Andover Conservation Commission. This BMP will be maintained by the DPW. The BMP is sized in accordance with Massachusetts DEP Stormwater Management Standards and Town of North Andover Bylaw Standards. (6) Expansion or construction of any accessory structure or expansion of any existing structure by less than twenty five(25)percent of the gross floor if the existing structure exceeds 2,500 square feet—The sum of the footprints of the existing structures does not exceed 2,500 square feet. As such,this use does not apply. (7) Expansion of any existing structure by less than fifty(50)percent of the gross floor area of the existing primary structure is less than 2,500 square feet and the primary structure will be connected to municipal sewer upon completion.—The sum of the footprints of the existing structures at the pump station is less than 2,500 square feet. The sum of the footprints of the proposed structure is approximately 50 percent larger than the existing,which meets the requirements of this section. The intention of the project is to allow installation of equipment to afford appropriate storage of wastewater and to allow for installation of larger capacity pumping equipment to handle the existing flows that will provide the necessary protection from potential sanitary sewer overflows at the station,which could result in contamination of Rea's Pond or Lake Cochichewick. The station will continue to convey wastewater to a location outside of the Watershed Protection District. Though these ancillary work items are detailed as uses allowed by Special Permit under the By-Law as detailed above,we are requesting a waiver of the Special Permit because the overall project, as a whole, is both an allowed use under the By-Law, as well as imperative to the preservation and protection of water quality in Lake Cochichewick,a the Town's main public water drinking supply. Town of North Andover(#225073.19) 2 Woodard&Curran 2015-04-10-Request for Watershed Protection SM Waiver.docx April 2,2015 In addition to this process,the project is subject to wetland protection regulations and a Notice of Intent (NO1) is being submitted to the North Andover Conservation Commission concurrent with this waiver request. As included in the NO1, erosion control measures will be in place and maintained throughout Ak the life of the project. This will meet the Watershed Protection By-Law, Subsection 8(1),Waiver of Watershed Protection District Special Permit. The DPW agrees that per the By-Law,the Town Planner Ago- will have the authority to stop construction if it is determined that proper erosion control is not in place. Abb, 414k If you have any questions, please contact the Project Manager,Jack Troidl,or me at(781)251-0200. 1 OODAR &CURRAN Sincerely, WOODARD&CURRAN Jason Kreil, P.E. Project Engineer Cc: Bruce Thibodeau, Director, DPW Timothy Willett,Operations Manager, DPW Jack Troidl, PM,W&C PN: 225073.19 i i I I Town of North Andover(#225073.19) 3 Woodard&Curran 2015-04-10-Request for Watershed Protection SM Waiver.docx April 2,2015