Commission continues Maple Street sidewalk review after stormwater questions

The Northborough Conservation Commission on March 9 continued review of a Notice of Intent for a proposed 2,100-foot ADA sidewalk on Maple Street between Ridge Road and Bartlett Street.

Scott Charpentier of the Department of Public Works described the project as a town effort to close a sidewalk gap that prevents students from safely walking to Bartlett Street and Algonquin athletic facilities. "Closing gaps for sidewalks around our community has been a priority," Charpentier said, and he noted the design work has been funded with ARPA dollars.

An engineer on the project (introduced as Kendra Robinson) told commissioners the alignment places the new sidewalk within the 100-foot wetland buffer zone, the 25-foot no-disturb setback and the 35-foot no-structure setback, but "the proposed sidewalk is not located within the footprint of any of the resource areas, and won't directly impact the resource areas." To address stormwater, the team proposed pretreatment devices, a sediment forebay sized to handle a 10-year event and a deep-sump catch basin. "We will construct a sediment forebay ... sized in accordance with the stormwater standards," Robinson said and agreed to confirm whether the new impervious area calculation includes adjacent existing roadway.

Commissioners raised technical questions about right-of-way width, telephone pole locations and whether concentrated flows would create erosion at the aqueduct crossing. Robinson said the right-of-way averages about 34 feet and the telephone poles are on the north side, "which is why we're kind of forced to go on the southern side." She said vegetation near the aqueduct should prevent erosion and that the design will minimize alterations to the existing buffer.

Chair Greg Young said the commission wants to see delineations on the ground and the engineer's follow-up on impervious-area calculations before a final decision. The commission voted unanimously to continue the Maple Street NOI to the April 13 meeting to allow time for those clarifications and to coordinate potential construction funding from Safe Routes to School grants.

The continuation means no construction approvals were issued at the March meeting; the applicants are expected to return with clarified stormwater calculations and flagging visible without snow.