A
93

US Water Score: A

Simi Valley, CA 93063

Ventura County · Population served: 94,738 · Data updated July 2026

Service-area evidence: EPA service-area records associate the listed system with this ZIP. Boundaries may still overlap or change.

Water Systems Serving This Area

🏔
VENTURA WWD NO. 8 - SIMI VALLEY
Surface water · Pop. 94,738
PWSID: CA5610023
🏔
GOLDEN STATE WATER COMPANY - SIMI VALLEY
Surface water · Pop. 45,128
PWSID: CA5610059

Contaminants Detected

ContaminantDetected LevelEPA MCLHealth GuidelineStatus
Lead
0.0
15 ppb 1 ppb Passed

Violation History (Last 5 Years)

1Total (5yr)
0Health-Based
1Major

Water Quality Summary

Understanding Your Water in Simi Valley

Tap water quality in Simi Valley, California (93063) receives an overall grade of A (Lower record-based concern) with a score of 93 out of 100, based on analysis of EPA compliance data, contaminant testing, and violation history. This is roughly in line with the California state average of 92. Compared to the national average (75), this area performs significantly better. The area is served by 2 water systems providing water to approximately 94,738 people, using surface water sources.

Your Score 93/100 A
vs State 0 pts above California avg (92)
vs National 18 pts above national avg (75)

What a Grade A Means

A score of 93/100 means public water-system records for Simi Valley, CA show relatively few concerns in the US Water Score model. This is an internal score, not an EPA safety rating, and it does not guarantee conditions at any specific tap.

Surface water: sourced from rivers, lakes, or reservoirs

Health Information

What These Contaminants Mean for You

⚠️

Lead in Your Water

Lead is a toxic metal that can leach from aging pipes and plumbing fixtures.

Health Effects

Even low levels of lead exposure can cause developmental delays in children, kidney damage, and cardiovascular effects in adults. The EPA action level is 15 ppb, but health experts recommend no safe level of lead in drinking water.

Common Sources

Lead enters water primarily through corrosion of lead service lines, lead solder, and brass fixtures — especially in homes built before 1986.

What You Can Do

If lead is detected above 1 ppb, consider using a certified lead-removal filter (NSF/ANSI 53) for drinking and cooking water. Run cold water for 30 seconds before use if water has been sitting in pipes.

Common Questions

Frequently Asked Questions

Based on public water-system records, Simi Valley, California receives an internal US Water Score grade of A (Lower record-based concern) with a score of 93/100. This indicates relatively few system-level concerns in our model, but it is not an EPA safety rating and does not guarantee tap conditions inside individual homes.

ZIP code 93063 is served by 2 water systems using surface water sources, providing water to approximately 94,738 people. Surface water systems are more susceptible to contamination from agricultural runoff, industrial discharge, and weather events, but typically undergo more extensive treatment including filtration and disinfection.

Lead levels in Simi Valley, California are 0.0 ppb, which is at or below the health guideline of 1 ppb. This is a positive result, though periodic testing is still recommended.

No PFAS ("forever chemicals") were detected in water systems serving Simi Valley, California during the most recent EPA monitoring period (UCMR5). However, not all water systems have been tested for all PFAS compounds, and new contamination can occur over time.

Water systems serving Simi Valley, California have received 1 violation in the last 5 years. Violations can range from paperwork issues (monitoring & reporting) to serious health-based violations where contaminant levels exceeded safe limits. Review the violation details above for specifics.

Water in Simi Valley, California shows no major contaminant concerns based on available data. A basic carbon filter can improve taste and reduce chlorine. For extra peace of mind, an NSF-certified pitcher filter or faucet-mount filter provides an affordable layer of protection.

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