Flooding and stormwater

Branchburg regulates stormwater under a state permit and is updating its floodplain rules. Two records carry the issue: the Stormwater Pollution Prevention Plan (SPPP) the Township files under its NJPDES municipal stormwater permit, and floodplain Ordinance No. 2026-1519, now before the Township Committee.

The floodplain ordinance. At its October 12, 2026 meeting the Committee introduced Ordinance No. 2026-1519, revising Article VIII, “Flood Plain Management,” of the Land Development Ordinance “to continue participation in the National Flood Insurance Program (NFIP).” Mayor James Schworn said the NJDEP requires it to comply with changes to the Flood Management Plan and to keep the Township in the program. It was introduced on motion of Mr. Young, seconded by Mr. Beatrice: 3–0 (Aye: Young, Beatrice, Schworn; Mrs. Columbus and Mr. Owens absent), and published October 13.

The text, in the Committee’s October 26 agenda packet:

• adopts FEMA’s Somerset County flood study and map panels by reference, listing November 13, 2026 as the effective date for eight of the panels (previously September 28, 2007), and requires the more restrictive of the effective maps, FEMA’s 2021 preliminary maps and other best available data;
• measures state-regulated flood hazard areas to NJDEP’s “Climate-adjusted Flood Elevation,” on the Raritan River and its North and South Branches, Holland Brook, Chambers Brook, the Lamington River and Pleasant Run, and notes that the state area can extend beyond FEMA’s mapped areas;
• sets the local design flood elevation generally at the best-available flood elevation plus one foot of freeboard, or the ASCE 24 elevation if greater;
• names the Township Zoning Officer the Floodplain Administrator, who issues floodplain development permits; and
• sets fines of up to $2,000 (up to $2,500, or $10,000 under state law, for dumping solid waste in a floodway or floodplain).

The October 26 agenda says the public hearing “will be carried to the meeting on November 9, 2026, to allow the Planning Board additional time to complete its consistency review,” and the Planning Board’s October 27 agenda lists that review. The minutes of both meetings had not yet been posted on October 31.

The permit and the plan. The Township’s SPPP, titled 2023 with an annual-review date of Sept. 10, 2024, identifies permit NJG0148539 and Township Engineer Doug Ball, P.E., as Stormwater Program Coordinator. It says all 89 miles of municipal roadway are swept three times a year and 10 miles of industrial roadway nine times a year, and that DPW inspects inlets annually and catch basins in January/February. Its mapping section links a 2018 outfall map as the most current. Its MS4 infrastructure inventory form, with totals due Jan. 1, 2026, listed outfalls, discharge points, interconnections, inlets, manholes, conveyance length and facilities as “TBD” at the 2024 review (pump stations 0, maintenance yards 2); the plan posted on the Township website still shows those entries. Its Watershed Improvement Plan form also reads “TBD.”

The stormwater ordinance. Ordinance 2024-1477, amending the Land Development Ordinance’s “Stormwater Control for Major Developments” section after NJDEP’s July 17, 2023 rule amendments, requires green infrastructure for erosion control, groundwater recharge, and runoff quantity and quality on major developments. The SPPP’s table dates its adoption Aug. 25, 2024; the ordinance scan’s closing page reads Aug. 26, 2024. The vote pages show a 5–0 first reading on July 22, 2024 and a final reading of four yes and one absent, as visually checked against the scan.

What residents can do. Read the ordinance text in the October 26 agenda packet on the Township’s Agendas/Minutes page, and speak at its public hearing, now set for the Committee’s Nov. 9, 2026 meeting (7 p.m., Municipal Building courtroom). The SPPP, outfall map and stormwater page are on the Township website; the Township Engineer can be asked for the current MS4 inventory.