Town Center Subbasin Study Report - Bellingham Massachusetts

Proposed Designs for Drainage Area S4: Thayer Street/Creek CentralS4 Thayer Street/Creek Central:Infiltration Basin Stormwater ControlDescription:THAYER STREETThis Drainage Area presented a unique challengebecause stormwater runoff is being mixed withflow from an intermittent stream in the drainageinfrastructure that runs below Thayer and MendonStreets. Ideally stormwater runoff should be collectedand treated prior to mixing with stream or river waters,this becomes more exigent when stream waters areflowing in stormwater drainage pipes. To address thischallenge, new piping is proposed to keep stream flowseparate from stormwater runoff. One set of pipes willconnect the stream from the south side of BrooksideLane to the wetland/stream on the north side ofMendon St, this pipe system will have minimal inletsfor stormwater runoff as only the two catch basinson Mendon St (near the intersection with Thayer St.)will connect to this pipe. A second pipe will carrystormwater runoff from Woodside Lane, BrooksideLane, Edgehill Lane and Thayer Street into a proposedinfiltration basin where it will be treated and infiltratedusing an infiltration basin and sediment forebay.Overflow will be directed into the adjacent wetland.Due to the proximity to the wetland, the infiltrationbasin and sediment forebay have been designed tocomply with the Mass DEP Stormwater ManagementStandards. 120