San Clemente, CA Environmental Rules: Flood Elevation Requirements (2026)

Chapter 15.76, the city's Flood Damage Prevention ordinance, applies to all areas of special flood hazard, flood-related erosion hazard and mudslide hazard identified on FEMA's Flood Insurance Study for Orange County and the accompanying Flood Insurance Rate Maps, first adopted November 26, 1979 and administered by a designated Floodplain Administrator. Under Section 15.76.120, no development can begin in these areas without a development permit, and Section 15.76.160(C)(1) sets the elevation rule for new residential construction and substantial improvements: the lowest floor, including any basement, must be built to or above the depth shown on the map in Zone AO, to or above the base flood elevation in Zone A, and in all other areas elevated to or above the base flood elevations, with the finished elevation certified by a registered engineer or surveyor and verified by the Community Building Inspector before the Floodplain Administrator signs off. Nonresidential construction can instead be floodproofed to a watertight standard under Section 15.76.160(C)(2).

Property in a coastal high hazard zone faces an added layer under Section 15.76.230: new construction and substantial improvements must be elevated on adequately anchored pilings or columns so the lowest horizontal structural member sits at or above the base flood elevation, the space below the lowest floor must stay free of obstructions or use breakaway walls, fill cannot be used for structural support, and altering sand dunes in a way that increases flood risk is prohibited outright. This local floodplain layer does not replace the California Coastal Act's separate coastal development permit requirement for shoreline property, which is administered under the city's certified Local Coastal Program and can be appealed to the California Coastal Commission.