Drinking water quality · 2022
· Verified
What's in Town of Hillsborough, CA tap water
11 contaminants were measured in the Town of Hillsborough, CA water system's 2022 annual report. Each is shown below against its federal limit.
- Reporting year
- 2022
- Contaminants measured
- 11
- Over federal limit
- 0
- Approaching the limit
- 0
- Service area
- CA
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-based1 violation on record · most recent May 2014resolved
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. | 42.9 ug/LAverageSystem-wide | None set | Within the limit |
| TTHMTotal trihalomethanes — a group of four chemicals (including chloroform) formed when chlorine reacts with natural organic matter. | 53.5 ug/LAverageSystem-wide | None set | Within the limit |
| BromateA disinfection byproduct formed when bromide-containing water is treated with ozone. | 1 ug/LAverageSystem-wide | None set | Within the limit |
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChloramineA longer-lasting disinfectant made by combining chlorine with ammonia. | 2.59 mg/LAverageSystem-wide | 4 mg/LMCL | Within the limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. | 0.0065 mg/L90th percentileAt the tap | 0.015 mg/LAction level | Within the limit |
| CopperA metal that enters water from corroding household plumbing. | 54 ug/L90th percentileAt the tap | None set | Within the limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| FluorideA mineral often added to drinking water to help prevent tooth decay. | 0.6 mg/LAverageSystem-wide | 4 mg/LMCL | Within the limit |
| NitrateA compound from fertilizer runoff, septic systems, and erosion of natural deposits. | Not detected mg/LAverageSystem-wide | 10 mg/LMCL | Within the limit |
Microbial
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Escherichia coli (E. coli)Escherichia coli — bacteria found in the gut of humans and animals. | 0AverageSystem-wide | None set | None detected |
| Giardia lamblia | 0.03AverageSystem-wide | None set | Detected — no federal limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| TOCTotal organic carbon — a measure of organic material dissolved in the water. | 1.5AverageSystem-wide | None set | Detected — no federal limit |
People also ask about Town of Hillsborough, CA's water
+Is Town of Hillsborough, CA tap water safe to drink in 2022?
Every one of the 11 contaminants measured in Town of Hillsborough, CA's 2022 Consumer Confidence Report is below its federal limit. "Safe" under the EPA's drinking-water standards is health-based, not aesthetic — but by those standards, no measured contaminant in this report exceeds its enforceable threshold. Individual health concerns (e.g. immunocompromised, infant, pregnancy) may warrant additional filtering regardless of compliance.
+What contaminants are in Town of Hillsborough, CA tap water?
11 contaminants were measured in Town of Hillsborough, CA's 2022 Consumer Confidence Report, spanning disinfection byproducts, inorganic chemicals, and metals. 4 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Where does the data on this page come from?
Every value is transcribed from Town of Hillsborough, CA's 2022 Consumer Confidence Report — the annual drinking-water report every U.S. public water utility is required by federal law to publish. The original source document is archived and viewable on this site. A water-quality report covers an entire service area, not a single address.
+How often is Town of Hillsborough, CA's water quality data updated?
Each U.S. public water utility publishes one Consumer Confidence Report per year, covering the prior calendar year's measurements. This page reflects the 2022 report; a new report will replace it once the utility publishes its next annual update.