Sonoma County updates local zoning to match FEMAmaps, directs staff to seek restudy of Lower Russian River and Marquess Creek

The Sonoma County Board of Supervisors on a 4-1 vote approved amendments to the county's official zoning database to add or adjust floodway (F1) and floodplain (F2) combining districts to match final Federal Emergency Management Agency flood insurance rate maps published July 31, 2024, and instructed staff to pursue a technical restudy of the Lower Russian River and Marquess Creek areas.

County staff told the board the update is required to remain in the National Flood Insurance Program and avoid a Jan. 31, 2025 deadline after which the county could be suspended from the NFIP if local regulations are not aligned with FEMA's maps. Supervisors also voted to direct Permit Sonoma to seek a focused restudy and a separate budget item to complete that work.

The board and staff framed the action as a compliance step to protect residents' access to federally backed flood insurance, federal disaster assistance and certain grant programs. Permit Sonoma staff said FEMA's mapping of the Russian River watershed had not been updated in more than 30 years and that newer hydrology and topographic data changed mapped boundaries.

Permit Sonoma planner Azzin Spalding told the board that the county implements FEMA maps by rezoning parcels…