Brockton, MA Environmental Rules: Flood Elevation Requirements (2026)

The overlay applies under § 27-36(4) to "all development in the district, including structural and non-structural activities, whether permitted by right or by special permit," layering Brockton's own standards on top of Mass. Gen. Laws ch. 131, § 40 and the floodplain sections of the state building code, 780 CMR. In the floodway shown on the FIRM, no fill, new construction or substantial improvement is allowed unless a registered professional engineer or architect certifies it will cause no increase in the flood level during a 100-year flood; where Zone A or AE has no mapped regulatory floodway, the city uses the best available federal, state or local data to block encroachments that would raise flood levels.

New and replacement water and sewer systems in the district must be designed to keep flood water out of the pipes and out of anything the pipes discharge. Anyone proposing to alter or relocate a watercourse must notify neighboring communities, the state NFIP coordinator at the Department of Conservation and Recreation, and FEMA's Region I office in Boston. A property owner who wants to build below the base flood elevation needs a special permit from the Zoning Board of Appeals, which may grant one only if it finds the land is not actually flood-prone, the action is consistent with the ordinance's purpose, it is the minimum relief necessary, and, on half-acre lots or smaller, the site is surrounded by existing structures already built below base flood level.

The application must include a site plan certified by a registered engineer, land surveyor or landscape architect showing existing and proposed contours at two-foot intervals, plus an environmental assessment; the Board circulates both to the building inspector, DPW's highway, sewer and water divisions, the planning board, the health department and the conservation commission for 14 days of written comment before it can decide.