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Is Modesto, CA tap water safe?

14 utilities serve Modesto, 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 14 utilities serving Modesto have a result above a legal limit or action level, or a health-based violation since 2016, in EPA’s and California’s records: City of Ceres and Riverdale Park Tract CSD.

City of Modesto, which serves the most people here, has 2 results above EPA’s new limit, which takes effect in 2029, 4 results above the health goal and 1 result above EPA’s health benchmark. The worst: PFOS at 26 ppt, above EPA’s new limit, which takes effect in 2029.

The water from City of Modesto is soft to very hard depending on the source, 35 to 388 mg/L (2 to 22.7 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 Modesto’s ZIP codes, from EPA’s estimates.

4 more utilities in Modesto

By EPA’s estimate, each serves fewer people in Modesto than those above.

What handles it

Each of these is certified, on a certifier’s listing, for a result above a line in City of Modesto’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 Modesto

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

  • Aemtek, Inc.

    Modesto, CA · about 5 miles

    Certified for bacteria

    (510) 979-1979

  • Institute of Environmental Health, Inc. dba IEH-JL Analytical

    Modesto, CA · about 6 miles

    Certified for bacteria, nitrate, minerals and other inorganics

    (209) 538-8111

  • Microbac Laboratories, Inc. - Turlock

    Turlock, CA · about 12 miles

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

    (707) 822-4649

All 145 certified labs for California

ZIP codes in Modesto

Which ZIP codes are in Modesto: 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 Modesto

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

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