Skip to content
TapBuff
ZIP

River Rd WS #25

What EPA’s and California’s records show in this utility’s water: nitrate, arsenic and other regulated chemicals; lead and copper; and violations since 2016, with the certification that handles each result.

Serves
65 people
Connections
19
Water source
Groundwater
Based in
Gonzales, CA
County
Monterey
Owner
Private
Hardness
Very hard
The ZIP code it serves

93926

The short answer

1 result is above EPA’s legal limit, and 1 more is above the health goal. The worst: Nitrate, above the legal limit. 37 health-based violations since 2016.

What handles it

What was found

Nitrate, uranium, chromium (total), arsenic and fluoride: California’s own results, samples taken from March 10, 2020 to Feb. 10, 2026, with EPA’s 2012 to 2019 file for earlier years.

Above the legal limit1

Nitrate

Comes from the source

Above the legal limit

96.1ppm

Highest sample; found in 24 of 24

2026, one sample: 38 ppm

From 2020 to 2026, 24 samples were above EPA’s legal limit of 10 ppm, the highest 96.1 ppm in 2025. The next sample at the same point, within 30 days, kept the average above the limit for one; 23 have no follow-up sample on file within 30 days. In 2026, the latest year on file, its one sample was 38 ppm, above the limit. EPA recorded violations for nitrate at this utility in 2020, 2021, 2022, 2023, 2024 and 2026. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 84.6 ppm, in 2018, and EPA recorded violations in 2012, 2015, 2016, 2017, 2018 and 2019.

What handles it

  • NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
  • NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”

Above the health goal1

Uranium

Comes from the source

Above the health goal

19.4ppb

Highest yearly average, 2021 to 2024

2024, one sample: 16.4 ppb

Averaged by year, the highest was 19.4 ppb, in 2021: below EPA’s legal limit of 30 ppb, but above its health goal of zero. In 2024, the latest year on file, its one sample was 16.4 ppb. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 20.9 ppb, in 2015.

What handles it

Below EPA’s limits1

Chromium (total)

Comes from the source

Below EPA’s limits

6.0ppb

Highest yearly average, 2024

Averaged by year, the highest was 6.0 ppb, in 2024, below EPA’s legal limit of 100 ppb. That is the only year on file. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 13 ppb, in 2015.

What handles it

3 compounds tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
  • Arsenic
  • Fluoride
  • Lead

What handles it

A certification covers specific claims, not a whole standard. Look for these claims on the certifier’s listing, not the box. Wording varies a little: NSF writes “Lead Reduction,” WQA just “Lead.”

  • NSF/ANSI 53

    Claim: Nitrate/Nitrite (30 ppm challenge)

    For: Nitrate

  • NSF/ANSI 58

    Claims: Nitrate/Nitrite Reduction, Uranium

    For: Nitrate, Uranium

    Other certifiers’ wording: Nitrate

At the tap, or for the whole house?

These come with the water itself, so a whole-house system certified for the same claims treats every tap and shower. A filter at the tap treats drinking water for much less. How whole-house systems compare.

Filters with those claims on a certifier’s listing

Disclosure: TapBuff earns a commission if you buy through some links on this page. It does not change which standard or filter we name. As an Amazon Associate, TapBuff earns from qualifying purchases. How TapBuff makes money

Compare five-year costs

The best reverse osmosis systems, ranked

Hardness

Very hard, 1070 mg/L (62.6 grains per gallon), at its one sampling point, in 2024.

Hardness is calcium and magnesium. EPA sets no limit for it: it shows up as scale on fixtures and in water heaters, and as soap that won’t lather. USGS calls water above 60 mg/L moderately hard, above 120 hard and above 180 very hard.

Softeners compared at 62.6 grains per gallon, salt includedSoftener or salt-free conditioner?California water hardness, utility by utility

Violations since 2016

Contaminant or ruleTypePeriodMeasuredStatus
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2026 to March 31, 202638 MG/LArchived
Lead and Copper Rule RevisionsThe required inventory of lead service lines was not completed or submitted on time.EPA: LSL InventoryOct. 17, 2024—Unaddressed
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2024 to Sept. 30, 202493 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2024 to June 30, 202486 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2024 to March 31, 202436 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleOct. 1, 2023 to Dec. 31, 202339 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2023 to Sept. 30, 202378 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2023 to June 30, 202381 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2023 to March 31, 202341 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleOct. 1, 2022 to Dec. 31, 202270 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2022 to Sept. 30, 202277 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2022 to June 30, 202273 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2022 to March 31, 202280 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleOct. 1, 2021 to Dec. 31, 202178 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2021 to Sept. 30, 202172 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2021 to June 30, 202180 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2021 to March 31, 202163 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleOct. 1, 2020 to Dec. 31, 202035 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2020 to Sept. 30, 202078 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2020 to June 30, 202084 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2020 to March 31, 202083 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleOct. 1, 2019 to Dec. 31, 201939 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2019 to Sept. 30, 201975 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2019 to June 30, 201982 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2019 to March 31, 201937 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleOct. 1, 2018 to Dec. 31, 201840 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2018 to Sept. 30, 201885 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2018 to June 30, 201873 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2018 to March 31, 201859 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleOct. 1, 2017 to Dec. 31, 201746 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2017 to Sept. 30, 201771.1 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2017 to June 30, 201772.9 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2017 to March 31, 201736.2 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleOct. 1, 2016 to Dec. 31, 201663 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJuly 1, 2016 to Sept. 30, 201673 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleApril 1, 2016 to June 30, 201669 MG/LArchived
NitrateA sample was above the legal limit, for a contaminant judged one sample at a time.EPA: Maximum Contaminant Level Violation, Single SampleJan. 1, 2016 to March 31, 201672 MG/LArchived
Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 1 monitoring or reporting violation not shown.

What this report can’t tell you

  • Everything else. Nitrate, uranium, chromium (total), arsenic and fluoride results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. River Rd WS #25’s own annual report, which it must send you every year, has the contaminants this page does not show.

  • Your own plumbing. Lead results are the 90th percentile across homes the utility samples. Your home’s service line, solder and fixtures decide yours. A certified lab test is the only way to know.

  • What it means for your health. This page reports what the records show and EPA’s limits and goals; it is not medical advice. If you are worried about a health effect, talk to a doctor or your local health department.

  • Anything after the latest data. SDWIS data is from 2026 Q3; UCMR 5 didn’t sample this utility; California’s results run from March 10, 2020 to Feb. 10, 2026.

Testing your own tap

River Rd WS #25’s results are for the water it sends out. What your own service line, solder and fixtures add shows up only in a test of your tap, by a lab California certifies.

The 3 labs California certifies closest to the area River Rd WS #25 serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.

  • Monterey County Consolidated Environmental Laboratory

    Salinas, CA · about 18 miles

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

    (831) 755-4516

  • Monterey Bay Analytical Services, Inc.

    Monterey, CA · about 24 miles

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

    (831) 375-6227

  • CM Analytical, Inc.

    Gilroy, CA · about 34 miles

    Certified for bacteria

    (408) 848-3619

All 145 certified labs for California

Sources

PWSID CA2701063. Rebuilt from EPA data on Oct. 18, 2026.

Towns it serves

Also in Monterey County

All California utilities

What to do next