Drinking water quality · 2023
· Verified
What's in City of Redwood City — Redwood City, Ca, CA tap water
30 contaminants were measured in the City of Redwood City — Redwood City, Ca, CA water system's 2023 annual report. Each is shown below against its federal limit.
- Reporting year
- 2023
- Contaminants measured
- 30
- 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.
- Treatment technique violationHealth-based1 violation on record · most recent Mar 2015resolved
- Maximum contaminant level exceededHealth-based1 violation on record · most recent Jan 2014resolved
Source: EPA SDWIS / ECHO. View the full federal record on EPA ECHO ↗
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorineA disinfectant added to drinking water to kill bacteria and viruses. | 2.76 mg/LAverageSystem-wide | 4 mg/LMCL | Within the limit |
Disinfection byproducts
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| HAA5Haloacetic acids — a group of five disinfection byproducts formed when disinfectants react with organic matter. | 34.75 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. | 42.42 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 |
| ChlorateA byproduct that can form during disinfection, especially when hypochlorite solutions degrade. | 144 ug/LAverageSystem-wide | None set | Detected — no federal limit |
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Dichloroacetic acidA haloacetic acid disinfection byproduct. | 19.8 ug/LAverageSystem-wide | None set | Within the limit |
| Trichloroacetic acidA haloacetic acid disinfection byproduct. | 12.86 ug/LAverageSystem-wide | None set | Within the limit |
| FluorideA mineral often added to drinking water to help prevent tooth decay. | 0.3 mg/LAverageSystem-wide | 4 mg/LMCL | Within the limit |
| Bromochloroacetic acidA mixed-halogen haloacetic acid disinfection byproduct. | 0.642 ug/LAverageSystem-wide | None set | 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 |
| BromideA naturally occurring salt found in source water. | Not detected ug/LAverageSystem-wide | None set | Detected — no federal limit |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| LeadA toxic metal that leaches into water from old service lines, solder, and plumbing fixtures. | 2.2 ug/L90th percentileAt the tap | None set | Within the limit |
| CopperA metal that enters water from corroding household plumbing. | 47 ug/L90th percentileAt the tap | None set | Within the limit |
| BoronA naturally occurring element from rock and soil. | 41 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| CalciumA naturally occurring mineral that contributes to water hardness. | 15 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| LithiumA naturally occurring element found in some groundwater. | Not detected ug/LAverageSystem-wide | None set | Detected — no federal limit |
| MagnesiumA naturally occurring mineral that contributes to water hardness. | 5.7 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| ManganeseA naturally occurring metal from soil and rock. | 1.75 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| SilicaA naturally occurring compound from sand and rock. | 7.5 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| SodiumA naturally occurring salt component. | 16 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| Strontium | 28 ug/LAverageSystem-wide | None set | Detected — no federal limit |
| Vanadium | 0.25 ug/LAverageSystem-wide | None set | Detected — no federal limit |
Other
Microbial
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Escherichia coli (E. coli)Escherichia coli — bacteria found in the gut of humans and animals. | 0 %AverageSystem-wide | None set | None detected |
| Giardia lamblia | 0.02AverageSystem-wide | None set | Detected — no federal limit |
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| AlkalinityA measure of the water's capacity to neutralize acids. | 60 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| HardnessA measure of dissolved calcium and magnesium minerals. | 60 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| pHA measure of how acidic or basic the water is. | 9.41AverageSystem-wide | None set | Detected — no federal limit |
| TOCTotal organic carbon — a measure of organic material dissolved in the water. | 1.5 mg/LAverageSystem-wide | None set | Detected — no federal limit |
People also ask about City of Redwood City — Redwood City, Ca, CA's water
+Is City of Redwood City — Redwood City, Ca, CA tap water safe to drink in 2023?
Every one of the 30 contaminants measured in City of Redwood City — Redwood City, Ca, CA's 2023 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 City of Redwood City — Redwood City, Ca, CA tap water?
30 contaminants were measured in City of Redwood City — Redwood City, Ca, CA's 2023 Consumer Confidence Report, spanning metals, inorganic chemicals, and disinfection byproducts. 3 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 City of Redwood City — Redwood City, Ca, CA's 2023 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 City of Redwood City — Redwood City, Ca, 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 2023 report; a new report will replace it once the utility publishes its next annual update.