Showing ordinances that apply to Loma Mar, CA
Loma Mar is an unincorporated community (population 134) in San Mateo County, California. Because Loma Mar is not an incorporated city, it does not have its own municipal code. Instead, San Mateo County ordinances apply directly to properties here. The grading & drainage rules below are the ones that govern your area.
San Mateo County requires a Grading Permit from Planning & Building for projects involving more than 250 cubic yards of cut and/or fill, or any grading on slopes over 20%, or grading within 100 ft of a watercourse. Drainage design must direct runoff away from structures and must not adversely redirect water onto neighboring properties. Retaining walls over 4 feet in height need separate engineering and permits. Pre-site erosion-control and tree-protection inspection may be required.
Grading permits are governed by the County's grading ordinance (Title 6) in conjunction with the California Building Code Chapter 18 (Soils and Foundations) and Appendix J (Grading). Threshold for permit: more than 250 cubic yards of cumulative cut and/or fill, OR any grading on slopes 20% or steeper, OR grading within 100 feet of a watercourse, OR cut/fill over 3 feet in height, OR any grading in the Coastal Zone. Grading permit applications require: topographic survey, grading plan showing existing and proposed contours, drainage plan, erosion and sediment control plan, geotechnical report (for sites on fill, steep slopes, or with liquefaction potential), hydrology analysis (if within 100 ft of watercourse), and tree protection/removal plan. Drainage from the site cannot be redirected onto a neighboring parcel in a way that causes damage (common-law nuisance plus Civil Code §§1008, 3479). Retaining walls over 4 feet in height or supporting a surcharge (driveway, slope) require structural engineering stamped by a California PE and a building permit. Large grading projects may need to implement the Construction General Permit (1+ acre disturbance) with a SWPPP. Compaction testing required for structural fill (typically 90-95% relative compaction).
Unpermitted grading: stop-work order, retroactive permit at 2-3x fee, fines $250-$2,500 per §1.04. Redirecting drainage onto neighbor: common-law nuisance plus corrective action required. Slope failure from improper grading: civil liability for damages plus Regional Board enforcement if sediment enters waterway. Unpermitted retaining wall over 4 ft: demolition or retroactive engineering.
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