Drinking water quality · 2023
· Verified
· PWSID CA2810004
What's in St. Helena, City of — St. Helena, Ca, CA tap water
Only 7 of 27 core regulated contaminants were reported for St. Helena, City of — St. Helena, Ca, CA. What was measured is not clean — but most of the picture is missing.
- !2 contaminants at or above a federal limit — worst is Turbidity at 4.6x
- !1 open monitoring or reporting violation
- !1 contaminant within 20% of a limit
- !7 of 27 core regulated contaminants reported — 20 never appear in this report
+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.
- −48 contaminants at or above a federal limit
- −4 contaminants within 20% of a limit
- −0 open health-based violations
- −3 open monitoring / reporting violations
- −6 health-based violations resolved in the last 5 years
- −19 core regulated contaminants never reported (7/27)
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
- Turbidity4.6× the federal limit4.6 NTU · limit 1 NTU
High turbidity can shelter microbes from disinfection; the EPA enforces it through a treatment-technique standard.
Higher than 95% of CA systems that report it · higher than 90% of U.S. systems
- HAA51.0× the federal limit61.71 ug/L · limit 60 ug/L
Long-term exposure above the federal limit is associated with an increased cancer risk.
Higher than 95% of CA systems that report it · higher than 95% of U.S. systems
- TTHM81% of the federal limit64.76 ug/L · limit 80 ug/L
Long-term exposure above the federal limit is linked to liver, kidney, and central-nervous-system effects and increased cancer risk.
Higher than 90% of CA systems that report it · higher than 85% of U.S. systems
+4 contaminants were measured and came in below the limitShow all
| Contaminant | Measured | Federal limit |
|---|---|---|
| Chlorine | 0.93 mg/L | 4 mg/L |
| Fluoride | 0.11 mg/L | 4 mg/L |
| Barium | 40 ug/L | 2000 ug/L |
| Lead | 0.0 mg/L | 0.015 mg/L |
What this report doesn't tell you
20 of the 27 contaminants a community water system normally reports do not appear anywhere in St. Helena, City of — St. Helena, 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-based9 violations on record · most recent Jul 2023resolved
- Treatment technique violationHealth-based2 violations on record · most recent Nov 2020resolved
- Monitoring & reporting1 violation on record · most recent Oct 20221 open
- Monitoring1 violation on recordresolved
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗