Stormwater Management: Altadena vs Palmdale
How do stormwater management rules compare between Altadena, CA and Palmdale, CA?
Altadena and Palmdale have similar restriction levels.
Altadena, CA
Los Angeles County
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.
View full Altadena rules →Palmdale, CA
Los Angeles County
Palmdale requires stormwater management for new development and significant property modifications. Runoff must be controlled on-site through retention, detention, or infiltration systems.
View full Palmdale rules →Key Facts Comparison
| Fact | Altadena | Palmdale |
|---|---|---|
| Authority | LA County Code Title 12 + State Water Board MS4 | - |
| Construction SWPPP | Required ≥1 acre disturbance | - |
| Illicit Discharge Hotline | (888) CLEAN-LA | - |
| New Development | - | Stormwater plan required |
| Runoff Control | - | On-site retention |
| Maintenance | - | Owner responsibility |
| Topic | - | Stormwater |
Highlighted rows indicate differences between cities.
Altadena FAQ
Can I hose my driveway into the gutter in Altadena?
Generally no — soapy or sediment-laden runoff into the storm drain violates the LA County NPDES MS4 permit and Title 12.
Palmdale FAQ
Do I need a stormwater plan for my project?
Generally required for new construction and major renovations that increase impervious surface area. Small residential projects may be exempt.
What is an illicit discharge?
Any non-stormwater substance entering the storm drain system, including paint, oil, chemicals, or sediment. Report violations to Palmdale public works.
Compare other topics
See how Altadena and Palmdale compare on other ordinance categories.
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