Is Lake Sherwood, CA tap water safe?
The short answer
None of the 5 utilities serving Lake Sherwood has a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and California’s records.
California Water Service Co - Westlake, which serves the most people here, has 1 result above the health goal. The worst: Lead at 3.0 ppb, above the health goal. Health goals are stricter than legal limits and are not enforced.
A town can be served by more than one utility, and some homes are on private wells. The name on your water bill tells you which is yours, and your ZIP code narrows it down. They are listed by how many people each serves in Lake Sherwood’s ZIP codes, from EPA’s estimates.
- Open report
California Water Service Co - Westlake
California · serves 19,544 people · about 630 in Lake Sherwood
1 result above the health goal. The worst: Lead at 3.0 ppb, above the health goal.
No health-based violations since 2016
- Open report
Las Virgenes MWD
California · serves 77,562 people · about 590 in Lake Sherwood
2 results above the health goal and 1 result above EPA’s health benchmark. The worst: Lithium at 15 ppb, above EPA’s health benchmark. Hardness: hard, 141 mg/L (8.2 grains per gallon).
No health-based violations since 2016
- Open report
Ventura Cwwd No. 38 - Lake Sherwood
California · serves 1,759 people · about 110 in Lake Sherwood
1 result above the health goal. The worst: Lead at 7.0 ppb, above the health goal.
No health-based violations since 2016
- Open report
Cal American Water Co
California · serves 66,809 people · under 100 in Lake Sherwood
1 result above the health goal and 1 result above EPA’s health benchmark. The worst: Lithium at 17.9 ppb, above EPA’s health benchmark.
No health-based violations since 2016
- Open report
City of Thousand Oaks Water Department
California · serves 54,770 people · under 100 in Lake Sherwood
Nothing in its records is above a health goal.
No health-based violations since 2016
What handles it
Each of these is certified, on a certifier’s listing, for a result above a line in California Water Service Co - Westlake’s water, which serves the most people here. Another utility’s report names what handles its own results.
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Brita Tahoe Pitcher with Elite Filter (OB60, OB06)
Pitcher
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 13, 2026
- IAPMO listing:NSF/ANSI 53checked Oct. 13, 2026
Certified for: Lead
Brita Everyday Pitcher with Elite Filter (OB46, OB06)
Pitcher
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 13, 2026
Certified for: Lead
PUR PLUS 11-Cup Pitcher (PPT111W)
Pitcher
- NSF listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 4, 2026
- WQA listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 4, 2026
- IAPMO listing:NSF/ANSI 42NSF/ANSI 53NSF/ANSI 401checked Oct. 4, 2026
Certified for: Lead
Water testing near Lake Sherwood
The 3 labs California certifies closest to Lake Sherwood, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Camrosa Water District Wastewater Laboratory
Camarillo, CA · about 10 miles
Certified for bacteria
Ventura County Public Health Laboratory
Oxnard, CA · about 16 miles
Certified for bacteria
Fruit Growers Laboratory, Inc.
Santa Paula, CA · about 18 miles
Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts, radioactivity
ZIP codes in Lake Sherwood
Which ZIP codes are in Lake Sherwood: Census 2020 relationship files. Which utilities serve them, and how many people: EPA SDWIS and EPA’s service area map. Each utility’s results: EPA UCMR 5, EPA SDWIS, and EPA’s and the state’s compliance monitoring, as its report lists them. How they are measured: methodology. Certified labs: California State Water Resources Control Board, ELAP accredited laboratories and their fields of accreditation; distances from the Census 2020 ZIP code tabulation area gazetteer.
Near Lake Sherwood
Other towns in Ventura County with a page of their own.
What to do next
- Read California Water Service Co - Westlake’s full reportEvery result with its dates, the violations, and the certification claim that handles each finding.Open the report
- Filters for LeadRanked by certification and what they cost over five years.The best water filters for lead, ranked
- On a private well?No utility tests a well. A certified lab test is the first step.How to test well water