Costa Mesa, CA Environmental Rules: Erosion Control (2026)

Costa Mesa has adopted Article 8 of Title 7 of the Codified Ordinances of the County of Orange, including the Grading Manual, in its entirety with specific local modifications. All construction and grading projects must implement erosion and sediment control measures to prevent soil from leaving the site and entering the storm drain system. Landscape plans must address grading, drainage, minimal runoff, erosion prevention, wind barriers, shade provisions, glare reduction, and water conservation. Projects disturbing one acre or more must file a Stormwater Pollution Prevention Plan (SWPPP) with the State Water Resources Control Board. Required BMPs during construction include silt fences, fiber rolls, stabilized construction entrances, dust control, and proper material storage. Grading permits are required for most earth-moving activities, though minor fills less than one foot deep on natural grade with slopes less steep than 5:1 that do not exceed 50 cubic yards and do not obstruct drainage courses may be exempt. Landscape planters with fill less than three feet deep and under 50 cubic yards may also be exempt.