Stormwater Management: El Monte vs Santa Clarita
How do stormwater management rules compare between El Monte, CA and Santa Clarita, CA?
Santa Clarita has fewer restrictions than El Monte.
El Monte, CA
Los Angeles County
El Monte regulates stormwater under Municipal Code Chapter 13.16 (Stormwater Management) and Chapter 13.20 (Low Impact Development), implementing the Los Angeles County MS4 NPDES Permit (Order R4-2021-0105, CAS004004). Only uncontaminated stormwater may enter the storm drain system.
View full El Monte rules →Santa Clarita, CA
Los Angeles County
Santa Clarita enforces LA County MS4 stormwater permit requirements. New development must manage runoff with LID features. The Santa Clara River watershed is a key concern.
View full Santa Clarita rules →Key Facts Comparison
| Fact | El Monte | Santa Clarita |
|---|---|---|
| Stormwater chapter | EMMC Chapter 13.16 | - |
| LID ordinance | Ord. 2840 (June 10, 2014), codified in Chapter 13.20 | - |
| MS4 permit | LA County Order R4-2021-0105 (NPDES CAS004004) | - |
| Watershed | Rio Hondo / San Gabriel River (WMP approved 2015) | Santa Clara River |
| Report illicit discharge | El Monte Public Works (626) 580-2087 | - |
| Max state civil penalty | $25,000/day (CA Water Code §13350) | - |
| MS4 Permit | - | LA County requirements apply |
| LID | - | Required for new development |
| Illicit Discharge | - | Prohibited |
Highlighted rows indicate differences between cities.
El Monte FAQ
Can I wash my car in my driveway in El Monte?
Occasional residential car-washing using a hose with shut-off and biodegradable soap is generally allowed; however, EMMC Chapter 13.16 prohibits any wash water containing detergents, oils, or chemicals from entering the storm drain. Wash on grass, or use a commercial car wash that recycles water.
Can I drain my pool to the street?
Only if dechlorinated, free of algaecides, and discharged to landscape - not directly to the storm drain. The MS4 Permit (R4-2021-0105) treats chlorinated pool water as an illicit discharge. Sanitary sewer discharge via an outside cleanout (with City approval) is preferred.
Do I need a SWPPP for my construction project?
Yes if your project disturbs 1 acre or more - California's General Construction Permit (Order 2022-0057-DWQ) requires a Stormwater Pollution Prevention Plan. Smaller El Monte projects must still comply with EMMC Chapter 13.20 LID requirements and may need an Erosion & Sediment Control Plan from the City Engineer.
Santa Clarita 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 Clarita public works.
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