River Road Mutual Water Company
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
- 26 people
- Connections
- 8
- Water source
- Groundwater
- Based in
- Modesto, CA
- County
- Stanislaus
- Owner
- Private
The short answer
Nothing in EPA’s and California’s records for this utility is above a health goal. That covers nitrate, arsenic and other regulated chemicals, plus lead and copper, not everything. No health-based violations on file since 2016.
What was found
Nitrate: California’s own results, samples taken from March 3, 2020 to June 17, 2026, with EPA’s 2012 to 2019 file for earlier years.
Below EPA’s limits1
Nitrate
Comes from the source
8.7ppm
Highest sample; found in 12 of 13
2026, one sample: 8.7 ppm
The highest sample, in 2026, was 8.7 ppm, below EPA’s legal limit of 10 ppm. That was also the latest year on file, and its one sample was 8.7 ppm. Earlier, from 2012 to 2019, EPA’s file shows a highest sample of 10.0 ppm, in 2012.
What handles it
- NSF/ANSI 58 look for “Nitrate/Nitrite Reduction”
- NSF/ANSI 53 look for “Nitrate/Nitrite (30 ppm challenge)”
One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Lead
Violations since 2016
No health-based violations on file with EPA since 2016. There are 2 monitoring or reporting violations: a sample missed, late or not reported.
What this report can’t tell you
Everything else. Nitrate results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. River Road Mutual Water Company’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 3, 2020 to June 17, 2026.
Testing your own tap
No lab California certifies is within 75 miles of the area River Road Mutual Water Company serves on the state’s list. Some take samples by mail; the state’s page lists them all.
All 145 certified labs for CaliforniaSources
- EPA UCMR 5 occurrence data, file of Oct. 15, 2026
- EPA SDWA bulk download (SDWIS federal data), 2026 Q3
- California State Water Resources Control Board, Division of Drinking Water, results from Jan. 1, 2020 to July 17, 2026, read Oct. 8, 2026
- EPA Six-Year Review 4 compliance monitoring data, 2012 to 2019, file of Feb. 5, 2024
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID CA5000020. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Nothing here is above a health goalIn EPA’s and California’s records for this utility. They don’t cover everything, which is why the next step matters.Every contaminant TapBuff tracks
- Get the utility’s own reportRiver Road Mutual Water Company must send you a water quality report every year. It covers contaminants this page does not show.How to read it
- Test your own tap for leadYour service line, solder and fixtures decide the lead at your faucet, not the utility’s average.Lead in your water: what to do
- Decide if you want a filter at allA filter for taste or chlorine is a preference, not a need. The standards say what each kind can do.NSF/ANSI standards, decoded