Chicopee, MA Environmental Rules: Stormwater Management (2026)

Chapter 231, Stormwater Management, was adopted by the City Council on 10-1-2024 as Ord. No. 24-78 and superseded the 2019 chapter. It exists to manage the municipal separate storm sewer system (MS4), prevent property damage, and protect water quality. Section 231-3 sets who needs a plan. Before any stormwater management permit issues for a listed development, the Superintendent must approve a stormwater management plan or a waiver of the requirement. The listed developments are multifamily residential developments involving three or more units, projects with a net increase in impervious surface area of 4,000 sq ft or more, land disturbance of one acre or more, including smaller activities in a larger common plan of development, and any other user the Superintendent deems to need a permit.

Under § 231-4, the plan must carry supporting computations, drawings and enough information to describe how runoff is managed from the entire development. Applicants can request a waiver from information requirements the Superintendent judges unnecessary. The stormwater management report must include pre- and post-development drainage calculations for the two-, 10-, 25- and 100-year, 24-hour storms, water quality calculations for total suspended solids and total phosphorus percent reduction, and the Massachusetts Department of Environmental Protection checklist stamped and signed by a Massachusetts professional engineer. Section 231-5 requires compliance with the Massachusetts Stormwater Standards and the MS4 permit, and applicants must implement low-impact development unless infeasible.

Section 231-7 bars three things: dumping any pollutant or non-stormwater discharge into the municipal storm drain system, watercourse or waters of the commonwealth; any illicit connection, even one that was permissible when made; and obstructing the flow into or out of the system without written prior approval from the Superintendent. Exemptions include waterline flushing, lawn watering, residential car washing, and dechlorinated pool water under one ppm chlorine that stands for one week. Section 231-8 requires immediate notice to the fire and police departments, Department of Public Works and Board of Health for oil or hazardous releases, and notice no later than the next business day for nonhazardous releases.