Consultants brief Select Board on MS4 compliance, infiltration trenches and permit timelines

On June 3 the Select Board received the town's annual MS4 permit compliance briefing from Weston & Sampson. The consultant, D. Schwarz, reviewed the six required control measures under the federal MS4 permit: public education and outreach, public participation, illicit-discharge detection and elimination, construction-site runoff control, post-construction stormwater management (BMPs), and pollution prevention/good housekeeping for municipal operations.

Schwarz said the town has advanced public outreach and has expanded catch-basin cleaning contracts and municipal sweeping; tracking data now guides cleaning frequency to meet permit thresholds (sump <50% full). He described ongoing wet-weather outfall screening and sampling, illicit-discharge investigations, and a prioritized list of municipal BMP retrofit opportunities. The town has a contract out to bid for 11 infiltration trenches designed to intercept high-phosphorus load areas; bid opening was scheduled this week with construction planned by Sept. 30 under current grant funding.

Schwarz flagged permit-year deadlines and evolving expectations from EPA: the current permit (administratively continued after official expiration) is likely to require more implementation and retrofit work in the coming cycle, and the town's next annual report is due Sept. 28. Staff and consultant said the town will need to map funding strategies for a likely increase in construction-focused compliance obligations.