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

50, the county's Floodplain Management chapter, applies wherever the Flood Insurance Study and Flood Insurance Rate Maps for Stanislaus County, first adopted in 1980 and amended since, place a parcel inside a flood hazard area. 310 requires the owner or an authorized agent to apply to the county's Floodplain Administrator, a role assigned to the Director of Public Works, and to obtain a floodplain development permit; the section makes clear that for projects involving a building or structure, the Administrator can require this floodplain permit in addition to, not instead of, the ordinary building permit.

No permit is issued until the applicant demonstrates compliance with the floodplain regulations and every other applicable code, and FEMA's Conditional Letters of Map Revision cannot substitute for that showing. 320, must describe the development and the parcel, state the proposed use, include a site plan and construction documents, and give a valuation of the work. 350 lets it lapse if the work hasn't started, or has stalled, for that long, though the Administrator may grant written extensions. 22.