Chelsea, MA Environmental Rules: Flood Zones (2026)

Section 34-184 states its purpose plainly: reduce threats to life and personal injury, avoid new hazards for emergency responders, prevent flood-driven contamination emergencies, protect utility service, and cut the costs of flood response, cleanup and property damage. The district's boundaries track FEMA's Flood Insurance Rate Map panels 25025C0017J, 25025C0018J and 25025C0019J, dated March 16, 2016, and cover special flood hazard zones A, AE, AH, AO, A99, V and VE. c. 131, § 40 as well as the state building code's (780 CMR) floodplain and coastal high-hazard provisions and the state's wetlands, inland wetlands, coastal wetlands and subsurface sewage disposal regulations.

Low-impact uses like farming, forestry, outdoor recreation, wildlife conservation and foot or bicycle paths are encouraged if they don't require structures, fill or material storage. General standards require new water supply systems to minimize flood-water infiltration and flatly prohibit placing mobile homes, mobile home parks or subdivisions anywhere in the district. In a designated floodway, encroachments including fill, new construction and substantial improvements are barred unless a registered professional engineer certifies the work won't raise flood levels during the 100-year flood. Review runs through the city clerk, who circulates 15 filed copies to the board of health, conservation commission, building inspector, department of public works, emergency management, fire, police and planning board.