Staff: EPA draft 'C2' stormwater permit could cover about 119 private Needham properties; working group weighs implications

Town staff briefed the Needham Stormwater Working Group on a draft U.S. Environmental Protection Agency general permit (referred to in the meeting as the "C2" GP) that would require commercial, industrial and institutional properties meeting specified impervious-cover thresholds to implement best management practices aimed at reducing phosphorus and other pollutants.

Staff presented a high-level inventory of privately owned properties in Needham that match EPA’s commercial/industrial/institutional codes and that appear to have at least one acre of impervious cover. Using the town’s property classifications and a rapid report run against the EPA appendices, staff reported the following counts: 67 commercial, 19 industrial and 33 institutional sites — about 119 properties in total — while noting that contiguous-parcel analysis (to confirm whether adjacent parcels owned by the same entity should be combined) remains incomplete.

How the C2 GP would apply: the draft permit is organized around impervious cover (not total land area) and, as discussed at the meeting, applies to privately owned sites in selected watersheds (staff cited the Charles River, Mystic and Neponset watersheds during the briefing). Multifamily housing of eight units or…