Calaveras County, CA Environmental Rules: Flood Elevation Requirements (2026)

Section 15.06.051.C sets separate elevation rules by zone. In AO zones, a structure must be elevated above the highest adjacent grade to a height two feet above the depth number shown on the Flood Insurance Rate Map, or at least four feet above the highest adjacent grade if the FIRM lists no depth number. In an unnumbered A zone, one without a published base flood elevation on the FIRM, the two-foot-above-BFE standard still applies, with the elevation determined by the floodplain administrator under § 15.06.042.C using the best available federal, state or other data.

Once a structure is finished, a registered civil engineer or licensed land surveyor must certify the lowest floor elevation, and the county building inspector must verify it, with that certification filed with the floodplain administrator. Nonresidential structures have an alternative under § 15.06.051.C.2: instead of elevating, they may be floodproofed watertight with walls substantially impermeable to water and components able to resist hydrostatic and hydrodynamic loads, certified by a registered civil engineer or architect. Manufactured homes carry their own two-foot-above-BFE elevation and anchoring standard at § 15.06.054, and recreational vehicles sited for more than one hundred eighty consecutive days must meet those same manufactured-home standards under § 15.06.055.