WENDELL PARK STORMWATER IMPROVEMENTS Spring 2018

Project Background 604(b) Water Quality Management Planning Grant Awarded to the Town in 2011 to identify potential locations which could be retrofitted with stormwater best management practices (BMPs) that will remediate polluted runoff. Began with 15 initial sites and narrowed down to 3 for further investigation and preliminary design including Wendell Park, Sumner Street, and Lafayette Street Further investigation at these sites included a survey to understand the layout of the existing infrastructure as well as test pits to determine groundwater elevations and soil types Using this information conceptual designs were developed to be used when construction funding could be made available The Town, in coordination with NepWRA, applied for construction grants to have these designs built and in 2016 an application to construct the design for Wendell Park was approved allowing the Town to move forward with the completion of the design

Project Overview – Area Drainage

Project Overview - Watershed

Project Overview Existing stormwater controls: 21 bypass pipes which channel water directly from the roadway into the stream

Project Design Install precast concrete tree filter boxes and catch basins in each of Wendell Park’s 6 drainage areas (0.20 – 0.30 acres) in order to collect and treat the stormwater runoff 2 1 3 4 5 6

Project Design – Tree Filter Boxes Tree Filter Box located at Lincoln Street and Brook Road in Milton installed in 2009 along with 5 other boxes in the vicinity of Kelly Field

Project Design – Tree Filter Boxes

Project Scope Expected to begin this spring and be completed by the end of May Install 6 Tree Filter Boxes & 6 Catch Basins All new structures will be connected to existing bypass pipes The installation of these structures is expected to reduce pollution into the brook by the following amount: Total Suspended Solids (TSS) by 2600lbs per year Phosphates (TP) by 8.4lbs per year Nitrates (TN) by 21.4lbs per year Fecal Coliform (FC) by 258 billion colonies per year Broken down by structure below: Roadway shoulders will be built up with loam and seed to help establish the gutter and direct water into new structures Dead vegetation and debris will be removed from the brook to allow for better flow

QUESTIONS?