Drinking water quality · 2024
· Verified
What's in Vacaville, CA tap water
33 contaminants were measured in the Vacaville, CA water system's 2024 annual report. Each is shown below against its federal limit — 1 sit at or above that limit.
- Reporting year
- 2024
- Contaminants measured
- 33
- Over federal limit
- 1
- Approaching the limit
- 0
- Worst contaminant
- Chromium, Hexavalent
- Service area
- CA
PFAS — EPA UCMR5 (2023–2025)
2 PFAS compounds above EPA limits in Vacaville, CA
The EPA finalized the first-ever federal drinking-water limits for six PFAS compounds in April 2024. These numbers come straight from EPA's UCMR5 lab dataset — every U.S. system serving more than 3,300 people tested every PFAS sample at an entry point to its distribution system. PFAS not listed below were either tested and not detected, or not yet sampled.
PFOS (Perfluorooctane sulfonic acid)
● Over EPA limit (2.5×)near national p90 (19.900000000000006 ng/L across detecting U.S. systems)
PFOA (Perfluorooctanoic acid)
● Over EPA limit (1.3×)below national p90 (13.649999999999999 ng/L across detecting U.S. systems)
PFHxS (Perfluorohexane sulfonic acid)
● Approaching limit (92%)near national p90 (12.049999999999997 ng/L across detecting U.S. systems)
Lithium
● Detected (no federal limit)near national p90 (76.59999999999991 mg/L across detecting U.S. systems)
PFBS
● Detected (no federal limit)below national p90 (13.909999999999979 ng/L across detecting U.S. systems)
Where your water comes from · EPA SDWIS
Vacaville, CA's drinking water comes from ground water, drawn from 15 sources.
Source
- WELL · 11
- DE MELLO WELL - STANDBY
- NBR WTP - NORTH BAY AQUEDUCT - RAW
- NBR WTP - PUTAH SOUTH CANAL - RAW
- + 1 more
Treatment
- WELL 16 - TREATED
- WELL 03 - TREATED
- WELL 05 - TREATED
- + 10 more
Distribution
Also buys water from CITY OF FAIRFIELD.
Historical readings · EPA Six-Year Review (2012–2019)
1 contaminant historically over EPA limits in Vacaville, CA
Every U.S. public water system reports compliance-monitoring data to EPA. The Six-Year Review releases the 2012–2019 window as a single dataset — here's what your system reported, year by year. Values shown are the highest detection per analyte per year, compared to the federal MCL.
| Contaminant | Worst detection | EPA limit | Years (2012–2019) |
|---|---|---|---|
CHROMIUM worst: 2013 | 0.152 mg/L 1.5× 15.2× the national p90 | 0.1 mg/L | '13'14'16'17'18'19 |
TTHM worst: 2016 | 0.076 mg/L 95% | 0.08 mg/L | '12'13'14'15'16'17'19 |
ARSENIC worst: 2012 | 0.0085 mg/L 85% near national p90 | 0.01 mg/L | '12'13'14'15'16'17'18'19 |
HAA5 worst: 2019 | 0.035 mg/L within | 0.06 mg/L | '18'19 |
NITRATE worst: 2012 | 4.81 mg/L within | 10 mg/L | '12'13'14'15'16'17'18'19 |
CADMIUM worst: 2019 | 0.0023 mg/L within near national p90 | 0.005 mg/L | '12'13'19 |
NITRATE NITRITE worst: 2018 | 3.8 mg/L within | 10 mg/L | '17'18'19 |
FLUORIDE worst: 2014 | 1 mg/L within | 4 mg/L | '12'13'14'15'16'17'18'19 |
BROMATE worst: 2016 | 0.0011 mg/L within | 0.01 mg/L | '16 |
BARIUM worst: 2014 | 0.14 mg/L within near national p90 | 2 mg/L | '14'17 |
URANIUM worst: 2018 | 0.00283 ug/L within below national p90 | 30 ug/L | '18 |
COPPER worst: 2014 | 0.107 mg/L below national p90 | — | '14'19 |
LEAD worst: 2014 | 0.0064 mg/L | — | '14'16'18'19 |
DBAA worst: 2018 | 0.0031 mg/L | — | '18'19 |
DCAA worst: 2018 | 0.016 mg/L | — | '18'19 |
TCAA worst: 2018 | 0.01 mg/L | — | '18'19 |
BROMODICHLOROMETHANE worst: 2012 | 0.0064 mg/L | — | '12'13'14'15'16'17'19 |
CHLOROFORM worst: 2012 | 0.022 mg/L | — | '12'13'14'15'16'17'19 |
DIBROMOCHLOROMETHANE worst: 2012 | 0.0032 mg/L | — | '12'13'14'15'16'19 |
Metals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Chromium, HexavalentHexavalent chromium ('chromium-6') — the more toxic form of chromium. | 14 ug/LAverage2023-2024 Groundwater | 10 ug/LMCL | At or above the limit |
+By source (2)— 2023-2024 Groundwater, Vwtp
| |||
| IronA naturally occurring metal common in groundwater. | 0.17 mg/LAverageNbr | 0.3 mg/LMCL | Within the limit |
+By source (3)— Nbr, 2023 Groundwater, Vwtp
| |||
| Chromium, TotalTotal chromium — the sum of all chromium forms, from natural deposits and industrial discharge. | 19 ug/LAverage2023-2024 Groundwater | 50 ug/LMCL | Within the limit |
+By source (3)— 2023-2024 Groundwater, Nbr, Vwtp
| |||
| ManganeseA naturally occurring metal from soil and rock. | 13 ug/LAverageNbr | 50 ug/LMCL | Within the limit |
+By source (3)— Nbr, Vwtp, 2023 Groundwater
| |||
| BoronA naturally occurring element from rock and soil. | 0.18 mg/LAverageVwtp | 1 mg/LNL | Within the limit |
+By source (3)— Vwtp, 2023 Groundwater, Nbr
| |||
| Vanadium | 3.1 ug/LAverageNbr | 50 ug/LNL | Within the limit |
+By source (2)— Nbr, Vwtp
| |||
| SeleniumA trace element from natural deposits and industrial discharge. | 2.3 ug/LAverage2023-2024 Groundwater | 50 ug/LMCL | Within the limit |
+By source (3)— 2023-2024 Groundwater, Vwtp, Nbr
| |||
| AluminumA common element sometimes used as a treatment coagulant. | 0.04 mg/LAverageNbr | 1 mg/LMCL | Within the limit |
+By source (3)— Nbr, 2023-2024 Groundwater, Vwtp
| |||
| SodiumA naturally occurring salt component. | 57 mg/LAverage2023 Groundwater | None set | Detected — no federal limit |
+By source (3)— 2023 Groundwater, Nbr, Vwtp
| |||
Physical & aggregate
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| OdorA measure of detectable smell in the water. | 1.4AverageNbr | 3MCL | Within the limit |
+By source (3)— Nbr, 2023 Groundwater, Vwtp
| |||
| Total Dissolved SolidsTotal dissolved solids — the combined content of all dissolved minerals and salts. | 373 mg/LAverage2023 Groundwater | 1000 mg/LMCL | Within the limit |
+By source (3)— 2023 Groundwater, Nbr, Vwtp
| |||
| Specific ConductanceA measure of how well water conducts electricity, which tracks dissolved mineral content. | 589Average2023 Groundwater | 1600MCL | Within the limit |
+By source (3)— 2023 Groundwater, Nbr, Vwtp
| |||
| HardnessA measure of dissolved calcium and magnesium minerals. | 177 mg/LAverage2023 Groundwater | None set | Detected — no federal limit |
+By source (3)— 2023 Groundwater, Nbr, Vwtp
| |||
| TOCTotal organic carbon — a measure of organic material dissolved in the water. | 2.1 mg/LAverageSystem-wide | None set | Detected — no federal limit |
| TurbidityA measure of cloudiness from suspended particles in the water. | 0.51Average2023 Groundwater | None set | Detected — no federal limit |
+By source (3)— 2023 Groundwater, Vwtp, Nbr
| |||
Disinfectants
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| ChlorineA disinfectant added to drinking water to kill bacteria and viruses. | 1.11 mg/LAverageSystem-wide | 4 mg/LMCL | Within the limit |
Radionuclides
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Gross AlphaGross alpha particle activity — a combined measure of alpha-emitting radioactive substances. | 3.1 pCi/LAverage2020 Groundwater | 15 pCi/LMCL | Within the limit |
+By source (2)— 2020 Groundwater, Vwtp
| |||
Inorganic chemicals
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| SulfateA naturally occurring mineral from rock and soil. | 42 mg/LAverageNbr | 500 mg/LMCL | Within the limit |
+By source (3)— 2023 Groundwater, Nbr, Vwtp
| |||
| ChlorideA naturally occurring salt compound. | 23 mg/LAverage2023 Groundwater | 500 mg/LMCL | Within the limit |
+By source (3)— 2023 Groundwater, Vwtp, Nbr
| |||
Microbial
| Contaminant | Measured | Federal limit | Status |
|---|---|---|---|
| Total ColiformA group of bacteria used as an indicator of overall water-system sanitation. | 0Highest single sampleNo. Of Detections | 5MCL | None detected |
People also ask about Vacaville, CA's water
+Is Vacaville, CA tap water safe to drink in 2024?
The 2024 Consumer Confidence Report for the Vacaville, CA water utility lists 1 contaminant at or above the federal limit: Chromium, Hexavalent. Whether that means the water is "unsafe" depends on which contaminant, how long the exposure, and individual health factors. The table on this page shows the measured value, the federal threshold, and the regulated statistic used for compliance.
+What contaminants are in Vacaville, CA tap water?
33 contaminants were measured in Vacaville, CA's 2024 Consumer Confidence Report, spanning metals, physical & aggregate, and inorganic chemicals. 24 have an enforceable federal limit; the rest are detected but unregulated. Every measured value, in the utility's own units, is on this page.
+Which contaminants exceed federal limits in Vacaville, CA tap water?
One contaminant in Vacaville, CA's 2024 report sits at or above the federal limit: Chromium, Hexavalent (1.4× the limit). The EPA enforces these limits against the regulated reporting statistic — typically a running annual average or 90th percentile — not a one-off sample spike.
+What is the worst contaminant in Vacaville, CA tap water?
The contaminant with the highest measured value relative to its federal limit in the 2024 report is Chromium, Hexavalent, at 1.4× the federal threshold. It belongs to the metals family of contaminants.
+Where does the data on this page come from?
Every value is transcribed from Vacaville, CA's 2024 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 Vacaville, 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 2024 report; a new report will replace it once the utility publishes its next annual update.