Rincon Water & Road Works
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
- 25 people
- Connections
- 27
- Water source
- Surface water bought from another system
- Based in
- Ventura, CA
- County
- Ventura
- Owner
- Private
The ZIP code it serves
The short answer
1 result is above EPA’s legal limit. The worst: Haloacetic acids (HAA5), above the legal limit. 6 health-based violations since 2016.
What was found
Haloacetic acids (HAA5) and total trihalomethanes (TTHM): California’s own results, samples taken from Feb. 27, 2020 to May 19, 2026, with EPA’s 2012 to 2019 file for earlier years.
Above the legal limit1
Haloacetic acids (HAA5)
Forms or is added in treatment
74.8ppb
Highest yearly average, 2020 to 2026
2026 average: 31 ppb
Averaged by year, the highest was 74.8 ppb, in 2023, above EPA’s legal limit of 60 ppb. Its highest single sample was 119 ppb. In 2026, the latest year on file, its four samples averaged 31 ppb. EPA recorded violations for haloacetic acids (HAA5) at this utility in 2020, 2023 and 2024. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 56.8 ppb, in 2019.
What handles it
No certification claim covers this compound yet.
Below EPA’s limits1
Total trihalomethanes (TTHM)
Forms or is added in treatment
63.8ppb
Highest yearly average, 2020 to 2026
2026 average: 29.5 ppb
Averaged by year, the highest was 63.8 ppb, in 2023, below EPA’s legal limit of 80 ppb. Its highest single sample was 92 ppb. In 2026, the latest year on file, its four samples averaged 29.5 ppb. EPA recorded no violation for total trihalomethanes (TTHM) at this utility since 2020. Earlier, from 2012 to 2019, EPA’s file shows a highest yearly average of 55.5 ppb, in 2019.
What handles it
- NSF/ANSI 53 look for “Trihalomethanes (TTHM) Reduction”
- NSF/ANSI 58 look for “Trihalomethanes (TTHM) Reduction”
One compound tested and not foundBelow the reporting level in every sample. Not found is not the same as zero.
- Lead
Violations since 2016
| Contaminant or rule | Type | Period | Measured | Status |
|---|---|---|---|---|
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2024 to March 31, 2024 | 0.063 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Oct. 1, 2023 to Dec. 31, 2023 | 0.077 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | July 1, 2023 to Sept. 30, 2023 | 0.078 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2023 to June 30, 2023 | 0.072 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | Jan. 1, 2023 to March 31, 2023 | 0.063 MG/L | Resolved |
| Total Haloacetic Acids (HAA5) | The running average was above the legal limit.EPA: Maximum Contaminant Level Violation, Average | April 1, 2020 to June 30, 2020 | 0.062 MG/L | Resolved |
| Health-based violations only. Resolved and archived mean the utility returned to compliance or the state closed the record. 5 monitoring or reporting violations not shown. | ||||
What this report can’t tell you
Everything else. Haloacetic acids (HAA5) and total trihalomethanes (TTHM) results here are California’s own from 2020 on, with EPA’s national file for 2012 to 2019. Rincon Water & Road Works’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 Feb. 27, 2020 to May 19, 2026.
Testing your own tap
The 3 labs California certifies closest to the area Rincon Water & Road Works serves, in a straight line. Call first: certification is test by test, and not every lab takes samples from homeowners.
Capco Analytical Services
Ventura, CA · about 42 miles
Certified for bacteria, nitrate, metals, minerals and other inorganics
Ventura County Public Health Laboratory
Oxnard, CA · about 46 miles
Certified for bacteria
Clinical Laboratory of San Bernardino II
Lompoc, CA · about 50 miles
Certified for bacteria
Sources
- 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
- Certified labs: California State Water Resources Control Board, ELAP accredited laboratories and their fields of accreditation, read Oct. 17, 2026; distances from the Census 2020 ZIP code tabulation area gazetteer
- Limits and goals: each contaminant’s page, with its EPA source.
- How this page is built: methodology.
PWSID CA5601137. Rebuilt from EPA data on Oct. 18, 2026.
What to do next
- Read up on Haloacetic acids (HAA5)What each one does to health, where it comes from, and the certification claim that addresses it.About Haloacetic acids (HAA5)
- Get the utility’s own reportRincon Water & Road Works 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