Mendocino County, CA Environmental Rules: Flood Zones (2026)

Inland unincorporated Mendocino County is governed by Mendocino County Code Title 22 (Land Usage), Chapter 22.17 (Floodplain Ordinance), administered by the Mendocino County Department of Planning and Building Services. Within the Coastal Zone, floodplain development is governed by Chapter 20.420 of the Coastal Zoning Code (Title 20, Division II). Both ordinances are designed to meet or exceed the criteria established in Title 44 Code of Federal Regulations Part 60, the federal floodplain management criteria adopted by FEMA for participation in the National Flood Insurance Program. Recent amendments (2025 Ordinance 4385) updated Chapter 22.17 to add definitions, coordinate with the California Building Standards Code, and expand the Floodplain Administrator's role with requirements for additional analyses to FEMA when there is a change to the base flood elevation or when development is proposed in the floodway. Special Flood Hazard Areas on FEMA Flood Insurance Rate Maps cover the Russian River corridor through Hopland and Talmage, the Navarro River, Big River near Mendocino village, the Noyo River through Fort Bragg, the Eel River, and the Garcia River near Point Arena. New construction in Zones A, AE, AO, and VE must have its lowest floor elevated to or above the Base Flood Elevation, and a FEMA Elevation Certificate prepared by a California licensed surveyor or civil engineer is required.