LA County operates under a regional MS4 permit issued by the LA Regional Water Quality Control Board. LA County Code Title 12 prohibits discharging non-stormwater (sediment, chemicals, paint, sewage, washwater) into storm drains.
LA County is a co-permittee of the Los Angeles MS4 NPDES Permit (Order No. R4-2021-0105). Title 12 of the LA County Code makes it unlawful to discharge any non-stormwater pollutant into a storm drain, gutter, or watercourse. Construction sites disturbing 1+ acre require coverage under the State Construction General Permit and a Stormwater Pollution Prevention Plan (SWPPP). New development and significant redevelopment must comply with Low Impact Development standards in Title 12. Reporting illicit discharges goes to LA County Public Works at (888) CLEAN-LA.
Illicit discharges are misdemeanors under Title 12, with fines up to $25,000/day plus restitution under the California Porter-Cologne Act.
Altadena, CA
LA County allows backyard chickens in R-1 zones in unincorporated areas (including Altadena) subject to coop setbacks under LA County Code Title 10 and Title...
Altadena, CA
LA County Code Section 10.32.010 prohibits dogs running at large in any public place or private property other than the owner's, unless restrained by a chain...
Altadena, CA
Trimming protected oak trees (≥8 in DBH) requires an Oak Tree Permit if the work enters the protected zone or removes >25% of crown. Street trees in the publ...
Altadena, CA
In Altadena's Very High Fire Hazard Severity Zones, grass and weeds must be kept under 3 inches under LA County Fire Code Title 32 defensible-space rules.
Altadena, CA
LA County Fire's Brush Clearance program also functions as the weed-abatement ordinance — vacant and improved lots must keep weeds and grasses cut to under 3...
Altadena, CA
Outdoor watering in Altadena (served by Lincoln Avenue Water Co., Las Flores Water Co., Rubio Cañon, and Kinneloa Irrigation District) is limited to 2 days p...
Side-by-side rule comparisons with other cities in Los Angeles County.
See how other cities in Los Angeles County handle stormwater management.
See how Altadena's stormwater management rules stack up against other locations.
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