Public water system record
California Water Service Co - Westlake
Serves Thousand Oaks and Oak Park, Ventura County, CA · 19,533 people served
Federal records show no health-based violations and no monitoring or reporting issues for California Water Service Co - Westlake in the last ten years.
System profile
- Health-based violations, last 10 years
- 0
- Resolved
- 0
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 0
Key facts
- California Water Service Co - Westlake buys its water from Calleguas Municipal Water Dist.
- Lead pipe inventory: 0 lead and 6,895 unknown out of 6,906 service lines.
Check whether California Water Service Co - Westlake serves your address
Health-based violations
Since October 2016Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.
None since October 2016, and no monitoring or reporting violations either.
Where the water comes from
California Water Service Co - Westlake buys its water from Calleguas Municipal Water Dist. It lists no wells or intakes of its own. It also has emergency connections to Las Virgenes MWD and Triunfo Water & Sanitation District. 2 other public water systems have emergency connections to California Water Service Co - Westlake.
Buys water from
- Calleguas Municipal Water Dist Thousand Oaks, CA
Emergency or part-time connections to
- Las Virgenes MWD Calabasas, CA
- Triunfo Water & Sanitation District Westlake Village, CA
Annual water quality report
California Water Service Co - Westlake must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.
Systems serving 10,000 or more people must mail or deliver the report to every customer, and from 2027 they must send it twice a year.
Find a posted report with EPA's Consumer Confidence Report search
Testing your own water
To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by California.
Certified drinking water labs by state EPA guidance for private wells