Drinking water quality · 2022
· Verified
· PWSID CA4810004
What's in City of Rio Vista — Rio Vista, Ca, CA tap water
Every one of the 10 core regulated contaminants reported for City of Rio Vista — Rio Vista, Ca, CA came in below its federal limit.
- !1 contaminant within 20% of a limit
- !10 of 27 core regulated contaminants reported — 17 never appear in this report
- ✓Nothing over a federal limit
- ✓No open federal violations
+How this score is calculated
Every system starts at 100. Points come off for measured levels, for the federal violation record, and for how much of the core regulated set the utility actually reported. All three inputs are the utility's own published numbers and EPA's own records.
- −0 contaminants at or above a federal limit
- −4 contaminants within 20% of a limit
- −0 open health-based violations
- −0 open monitoring / reporting violations
- −0 health-based violations resolved in the last 5 years
- −14 core regulated contaminants never reported (10/27)
A 90–100 · B 80–89 · C 70–79 · D 60–69 · F below 60. A system reporting under a third of the core set is capped at C however clean its numbers look — a short report is not a clean bill of health.
Full grading methodology, constant for constant →What to worry about
- Arsenic90% of the federal limit9 ug/L · limit 10 ug/L
A known human carcinogen; long-term exposure is linked to skin, bladder, and lung cancer.
Higher than 95% of CA systems that report it · higher than 95% of U.S. systems
+16 contaminants were measured and came in below the limitShow all
| Contaminant | Measured | Federal limit |
|---|---|---|
| Gross Alpha | 4.27 pCi/L | 15 pCi/L |
| Nitrate | 1.8 mg/L | 10 mg/L |
| TTHM | 11 ug/L | 80 ug/L |
| Nitrate Nitrite | 1.2 mg/L | 10 mg/L |
| Selenium | 5 ug/L | 50 ug/L |
| Fluoride | 0.3 mg/L | 4 mg/L |
| Copper | 0.05 mg/L | 1.3 mg/L |
| Chlorine | 0.05 mg/L | 4 mg/L |
| Boron | 1.1 mg/L | — |
| Lead | 0.0 mg/L | 0.015 mg/L |
| Manganese | 18 ug/L | — |
| Vanadium | 0.503 mg/L | — |
| Dinoseb | Not detected ug/L | 7 ug/L |
| Pentachlorophenol | Not detected ug/L | 1 ug/L |
| Picloram | Not detected ug/L | 500 ug/L |
| Uranium | 1.826 pCi/L | 20 pCi/L |
What this report doesn't tell you
17 of the 27 contaminants a community water system normally reports do not appear anywhere in City of Rio Vista — Rio Vista, Ca, CA's data. Absent is not the same as absent-from-the-water — it means nobody published a number.
+Full detail: PFAS testing, water source, historical monitoring, and the federal violation record
Compliance history
Federal Safe Drinking Water Act violation & enforcement records (EPA SDWIS). A violation is a regulatory determination by the state or EPA — separate from the measured levels above.
- Maximum contaminant level exceededHealth-based3 violations on record · most recent Jan 1995resolved
- Monitoring1 violation on recordresolved
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗