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Is Angwin, CA tap water safe?

5 utilities serve Angwin, by EPA’s records. Here is what EPA’s and California’s records show for each, against the legal limits and the stricter health goals.

Matched to your utility using EPA records.

The short answer

2 of the 5 utilities serving Angwin have a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and California’s records: Howell Mountain Mutual Water Company and La Tierra Heights Mutual.

Howell Mountain Mutual Water Company, which serves the most people here, has 1 result above the legal limit and 1 result above the health goal. The worst: Total trihalomethanes (TTHM) at 88 ppb, above the legal limit.

The water from Howell Mountain Mutual Water Company is soft, typically 27 mg/L (1.6 grains per gallon). How California’s water compares.

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 Angwin’s ZIP codes, from EPA’s estimates.

What handles it

Each of these is certified, on a certifier’s listing, for a result above a line in Howell Mountain Mutual Water Company’s water, which serves the most people here. Another utility’s report names what handles its own results.

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Every claim, and more filters, in the full report

Water testing near Angwin

A utility tests the water it sends out. A test of your own tap shows what your pipes add, and on a private well it is the only test there is. It takes a lab California certifies.

The 3 labs California certifies closest to Angwin, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Sonoma County Public Health Laboratory

    Santa Rosa, CA · about 16 miles

    Certified for bacteria

    (707) 565-4711

  • Brelje and Race Laboratories, Inc.

    Santa Rosa, CA · about 17 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, organic chemicals, disinfection byproducts

    (707) 544-8807

  • K Prime, LLC.

    Santa Rosa, CA · about 20 miles

    Certified for bacteria, nitrate, lead and copper, metals, minerals and other inorganics, PFAS

    (707) 527-7574

All 145 certified labs for California

ZIP codes in Angwin

Which ZIP codes are in Angwin: 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 Angwin

Other towns in Napa County with a page of their own.

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