Stormwater Management: Altadena vs Santa Monica
How do stormwater management rules compare between Altadena, CA and Santa Monica, CA?
Altadena has fewer restrictions than Santa Monica.
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 →Santa Monica, CA
Los Angeles County
Santa Monica operates a stormwater utility under the municipal code with user fees on all parcels. The city promotes runoff conservation and sustainable management for water sustainability. LID and stormwater harvesting are strongly encouraged.
View full Santa Monica rules →Key Facts Comparison
| Fact | Altadena | Santa Monica |
|---|---|---|
| Authority | LA County Code Title 12 + State Water Board MS4 | - |
| Construction SWPPP | Required ≥1 acre disturbance | - |
| Illicit Discharge Hotline | (888) CLEAN-LA | - |
| Stormwater Utility | - | User fee on all parcels |
| Runoff Conservation | - | SMMC Ch. 7.10 |
| LID | - | Encouraged for all development |
| Water Sustainability | - | Rainwater/stormwater reuse promoted |
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.
Santa Monica 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 Santa Monica public works.
Compare other topics
See how Altadena and Santa Monica compare on other ordinance categories.
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