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🌍 Environmental Rules/Stormwater Management

Stormwater Management: Fillmore vs Simi Valley

How do stormwater management rules compare between Fillmore, CA and Simi Valley, CA?

Fillmore and Simi Valley have similar restriction levels.

Fillmore, CA

Ventura County

Some Restrictions

Fillmore participates in the Ventura County Municipal Separate Storm Sewer System (MS4) Permit program. New development and redevelopment must implement Low Impact Development (LID) practices. Illicit discharge to the storm drain system is prohibited.

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Simi Valley, CA

Ventura County

Some Restrictions

Simi Valley enforces stormwater management regulations under the Ventura County Municipal Separate Storm Sewer System (MS4) permit. Construction projects must implement best management practices to prevent pollutants from entering storm drains.

View full Simi Valley rules →

Key Facts Comparison

FactFillmoreSimi Valley
MS4 PermitVentura County co-permittee-
LID RequiredNew development/redevelopmentNew development post-construction
WatershedSanta Clara River-
Illicit DischargeProhibited to storm drains-
CWA StatusRiver impaired under §303(d)-
Permit Trigger-1+ acre disturbance needs CGP
SWPPP Required-For qualifying construction projects
Storm Drain Discharge-Non-stormwater prohibited

Highlighted rows indicate differences between cities.

Fillmore FAQ

Where does stormwater go in Fillmore?

Storm drains in Fillmore flow to the Santa Clara River. The river is listed as impaired under the Clean Water Act, making stormwater quality management especially important.

Can I wash my car in the driveway in Fillmore?

Car wash runoff flowing into storm drains is considered an illicit discharge. Wash your car on grass or a permeable surface where water can soak in, or use a commercial car wash that recycles water.

What LID measures are required for new construction?

New development must incorporate Low Impact Development features such as bioretention areas, permeable paving, rain gardens, or infiltration systems per the Ventura County MS4 Permit requirements.

Simi Valley FAQ

Do I need a stormwater plan for my construction project?

Projects disturbing one acre or more need a Construction General Permit and SWPPP. Smaller projects still must implement erosion and sediment control BMPs during construction.

Can I wash my car in the driveway?

Car washing on pervious surfaces that absorbs runoff is generally acceptable. Wash water should not flow into storm drains. Use a commercial car wash or wash on a lawn where water can infiltrate.

What is LID and does it affect my project?

Low Impact Development requires new construction to manage stormwater on-site through features like permeable pavement, rain gardens, or infiltration. It applies to new development and significant remodels.

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