Chittenden County, VT Environmental Rules: Flood Zones (2026)

Vermont counties have no flood-plain authority - regulation occurs at the state and town level. Statewide framework: 24 V.S.A. §4424 authorizes municipalities to adopt flood-hazard area bylaws and requires them to do so to participate in the FEMA National Flood Insurance Program; 10 V.S.A. Chapter 32 (Flood Hazard Areas) provides additional state oversight; and Act 121 of 2024 (Flood Safety Act, S.213, signed May 31, 2024) creates Vermont's first statewide regulation of River Corridors - the area where rivers naturally meander. Under Act 121, the Agency of Natural Resources will require permits for new development in River Corridors of streams with watersheds of 2 square miles or greater, effective January 1, 2028. The Act also strengthens dam safety regulation, enhances wetland protections (which slow floodwaters), and creates funding for dam removal and repair. Chittenden County's primary flood risks are Lake Champlain (FEMA Special Flood Hazard Area Zone AE along the lakeshore in Burlington, Colchester, South Burlington, Shelburne, and Charlotte) and the Winooski River (Zone AE through Winooski, Burlington's Intervale, Essex Junction, Williston, and Richmond). Vermont's standard exceeds NFIP minimums by requiring 1 foot of freeboard (finished floor at least 1 foot above the base flood elevation) under the Vermont Agency of Natural Resources model bylaws; many Chittenden County towns require 2 feet. Burlington, Winooski, and Essex Junction enforce their own flood-hazard bylaws. Act 250 (10 V.S.A. Chapter 151) Criterion 1(D) also requires that developments meeting Act 250 jurisdiction not significantly affect the floodway or floodway fringe.