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Is Los Osos, CA tap water safe?

3 utilities serve Los Osos, 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

None of the 3 utilities serving Los Osos has a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and California’s records.

Los Osos Community Services District, which serves the most people here, has 2 results above EPA’s new limit, which takes effect in 2029, 3 results above the health goal and 1 result above EPA’s health benchmark. The worst: PFOA at 14.7 ppt, above EPA’s new limit, which takes effect in 2029.

The water from Los Osos Community Services District is soft to very hard depending on the source, 59 to 331 mg/L (3.5 to 19.4 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 Los Osos’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 Los Osos Community Services District’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 Los Osos

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 Los Osos, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Abalone Coast Analytical, Inc.

    San Luis Obispo, CA · about 10 miles

    Certified for bacteria

    (805) 595-1080

  • Fruit Growers Laboratory, Inc.

    San Luis Obispo, CA · about 10 miles

    Certified for bacteria

    (805) 783-2940

  • County of San Luis Obispo Public Health Laboratory

    San Luis Obispo, CA · about 11 miles

    Certified for bacteria

    (805) 781-5507

All 145 certified labs for California

ZIP codes in Los Osos

Which ZIP codes are in Los Osos: 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 Los Osos

Other towns in San Luis Obispo County with a page of their own.

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