Ulster County, NY Environmental Rules: Stormwater Management (2026)

NYS DEC SPDES General Permit GP-0-20-001 requires a Stormwater Pollution Prevention Plan (SWPPP) for any construction disturbing 1 acre or more (or less if part of a larger common plan). Notice of Intent (NOI) must be filed with DEC before ground disturbance. SWPPPs must follow the NYS Stormwater Management Design Manual and include erosion/sediment controls during construction and post-construction runoff reduction. MS4 communities (City of Kingston, Town of Ulster, Town of Esopus as census-designated urbanized areas) operate under SPDES MS4 General Permit GP-0-15-003 requiring public education, illicit discharge detection, construction site runoff control, and post-construction stormwater management. Municipalities pass local stormwater laws with plan review and inspection. NYC DEP Watershed Rules (18 NYCRR Part 18) apply in Shandaken, Olive, Hardenburgh, and Denning — stricter standards for subsurface sewage, stormwater, and impervious surfaces to protect the Ashokan and related reservoirs serving 9 million New Yorkers with unfiltered water. Any new development exceeding 2 acres or approaching a watercourse requires DEP Stormwater Pollution Prevention Plan review in addition to NYS SWPPP. DEC and DEP inspections enforce compliance. Post-Hurricane Irene (2011), Ulster towns in the Esopus corridor enhanced stormwater requirements including buffer protection and culvert sizing.