LACO Title 22.110.090 governs Hillside Management Areas in unincorporated LA County, applying a slope-density formula, requiring vegetation protection, and triggering geotechnical review and CEQA evaluation for steep-lot development.
The Hillside Management Area (HMA) regulations under LACO Title 22.110.090 cover unincorporated parcels mapped on the county's hillside layer. Maximum residential density is calculated through a slope-density formula: as average parcel slope increases, the allowed dwelling units per acre drops, with very steep parcels (over 50 percent slope) often limited to one unit per several acres. Significant native vegetation, ridgelines, and prominent landforms are protected. Projects trigger geotechnical and soils reports, grading review, haul-route approval, and CEQA evaluation for slope stability, fire risk, and biological resources. Many hillside parcels also lie inside Very High Fire Hazard Severity Zones, layering Title 32 fire code rules on top.
Unpermitted grading, exceeding density limits, removing protected vegetation, or skipping geotech review triggers stop-work orders, daily fines, and required restoration to pre-violation conditions.
Norwalk, CA
California PRC §4291 requires 100-foot defensible space in fire hazard zones. Norwalk may impose additional clearance requirements.
Norwalk, CA
Norwalk requires grading permits for significant earth-moving work. Drainage must not redirect water onto neighboring properties. Proper grading prevents ero...
See how Norwalk's hillside overlay rules rules stack up against other locations.
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