Murrieta, CA Environmental Rules: Erosion Control (2026)

160 requires that all grading plans, regardless of submittal date, include an erosion and sediment control plan designed to limit erosion of disturbed portions of a property and minimize soil transport onto adjacent properties, streets, storm drains or drainage ways, prepared per Subarticle 6 of the city's Grading Manual. 390 fills in the operative standards: projects must reduce pollutants to the "maximum extent practicable (MEP)," and any project disturbing one acre or more of soil must generate a Stormwater Pollution Prevention Plan (SWPPP) under the State General Construction Permit.

Permittees must minimize or phase grading during the wet season, prioritize erosion prevention over sediment controls, minimize exposure time of disturbed soil, temporarily stabilize and reseed disturbed areas quickly, permanently re-vegetate as early as feasible, and stabilize all slopes. No grading work is allowed on a permitted site until the city engineer approves an erosion and sediment control plan, and BMPs shown on the SWPPP must be implemented before October 1 of each year to cover the rainy season. The permittee remains responsible for erosion and sediment control until the city engineer accepts the completed grading, a duty that extends to completed and occupied lots, and materials for emergency temporary devices must be stockpiled on site with workers available during the rainy season. The city engineer can halt grading entirely if erosion, mud flow or sediment discharge threatens downstream properties, drains or public facilities.