Hawthorne, CA Environmental Rules: Erosion Control (2026)

150 requires every construction project in the city, from land clearing or demolition through issuance of a certificate of occupancy, to apply best management practices drawn from Tables 7 and 8 of the MS4 NPDES permit so that stormwater runoff carrying sediment, construction materials or other pollutants from the site and adjacent staging, storage or parking areas is reduced to the maximum extent practicable. Required measures include structural controls such as sediment barriers, plastic sheeting, detention ponds, hydromulch, storm drain inlet protection, fiber rolls, chemical treatment, filters and berms, plus wind erosion controls like silt fencing and tracking controls such as entrance/exit stabilization or tire washing when needed.

Excavated soil must be located on site to minimize sediment reaching the street, drainage facilities or neighboring properties, with soil piles bermed or covered until used or hauled away. Washing construction vehicles or equipment on site is barred if wash water could run off the site into the municipal storm sewer, and trash receptacles must be kept from accumulating litter that migrates off site. 150(A)(7) separately requires that erosion from slopes and channels be controlled through an effective combination of best management practices. 160 requires the property owner to certify that these BMPs will be implemented, and requires the city manager, public works director, planning director or director of building and safety to require submission of an erosion and sediment control plan consistent with the MS4 NPDES permit for city review and approval. 150(A)(6) to recover program costs.