Chino, CA Environmental Rules: Flood Zones (2026)

Floodplain development in Chino's SFHAs is regulated under California Code of Regulations Title 23 Division 5 (CCR Title 23 §2900 et seq.), which sets the statewide NFIP floor. Within a designated SFHA, the lowest floor of new or substantially improved residential structures must be elevated at least 1 foot above Base Flood Elevation (BFE). Non-residential structures may instead be dry-floodproofed with engineered certification. Substantial improvement — cumulative work valued at 50% or more of the structure's pre-improvement market value — triggers full compliance, as does substantial damage. Fill, grading, or structures in the regulatory floodway are prohibited if they cause any increase in flood elevations (no-rise certification required). The Prado Dam Project, operated by the U.S. Army Corps of Engineers Los Angeles District, can raise the maximum inundation pool to 566 ft above sea level; properties below that elevation in southern Chino have been encumbered by federal flowage easements since the 2003-2008 dam modification project. Letters of Map Amendment (LOMA) and Map Revisions (LOMR) are processed through FEMA. Floodplain development permits are issued by Chino Building & Safety / Engineering before any building or grading permit can be released in an SFHA.