10 county-level rules, plus city-specific rules for 4 cities in Westchester County, New York.
Verified from official government sources
Westchester County operates countywide MS4 under NYS SPDES GP-0-15-003. All 43 municipalities must enforce stormwater rules including illicit discharge bans and construction site controls.
Erosion and sediment control required on construction sites disturbing 1+ acre under NYS SPDES General Permit GP-0-20-001. Municipalities enforce via MS4 program.
Westchester waterfront communities use Local Waterfront Revitalization Programs (LWRPs) coordinated with NYS DOS and DEC. Coastal Erosion Hazard Area and tidal wetlands permits required.
Westchester has AE/VE zones along Long Island Sound (Rye, Mamaroneck, New Rochelle, Larchmont) and Hudson River (Yonkers, Hastings, Tarrytown). County participates in NFIP via municipal partners.
Grading and drainage regulated at municipal level via local codes. Many Westchester towns require grading permits for significant earthwork and prohibit redirecting runoff onto neighbors.
New York State Environmental Conservation Law and DEC regulations cap heavy-duty vehicle idling at five minutes statewide, and Westchester villages such as Mount Kisco enforce parallel limits for all vehicles near schools and residential areas.
Several Westchester villages including Larchmont, Mamaroneck, Scarsdale, and Bronxville restrict gas-powered leaf blowers seasonally or year-round, while county noise guidance under Chapter 484 supports municipal action on yard-equipment noise.
Westchester County declared a climate emergency and adopted a Climate Action Plan with countywide greenhouse-gas reduction targets, building electrification goals, and resilience planning under Sustainability Code Chapter 700.
Westchester County requires departments to prioritize environmentally preferable products, recycled-content paper, EnergyStar equipment, and low-emission vehicles when feasible, under its sustainable procurement administrative directive tied to Chapter 700.
Westchester County's sustainability planning encourages cool-roof installations, expanded tree canopy, and reflective surfaces in dense urban centers like Yonkers, Mount Vernon, and New Rochelle to mitigate the urban heat island effect.
4 cities in Westchester County have their own environmental rules rules. Each link goes to that city's dedicated page with code citations.
5 verified rules • Coastal Development, Erosion Control
5 verified rules • Coastal Development, Erosion Control
5 verified rules • Coastal Development, Erosion Control
5 verified rules • Coastal Development, Erosion Control
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Westchester County Ordinance Hub →