Napa Water Quality
California
According to EPA SDWIS, Napa, California is served by 16 community water systems covering about 87,913 people. The same extract lists 72 health-based violation records, most recently coded 5200 in 2024. Counts are historical EPA registry rows, not a current compliance or drinkability score.
Drinking water in Napa, California is delivered through 16 EPA-regulated community water systems serving an estimated 87,913 people. Each system is tracked in the EPA Safe Drinking Water Information System (SDWIS) under the Safe Drinking Water Act, which requires testing for regulated contaminants, consumer notification of violations, and publication of an annual Consumer Confidence Report.
PlainEnviro's health-based SDWIS extract shows 72 violation records across the 16 active community systems shown here. Monitoring and reporting records are not present in the extract. The records carry 6 distinct EPA contaminant codes: LEAD AND COPPER RULE REVISIONS, Revised Total Coliform Rule, Selenium, TTHM, Total Haloacetic Acids (HAA5) and 1 others. 2 TRI-reporting industrial facilities are also located within the city limits.
A past EPA health-based registry row does not describe water delivered today or current compliance status; utilities notify customers and remediate under state primacy oversight when required. For current water-quality status and treatment practices, review your local utility's most recent Consumer Confidence Report or contact the California drinking water program. All records above reflect federal EPA SDWIS data and are not independently verified against state databases.
Community Water Systems
| System Name | Pop. Served | Violations | Status |
|---|---|---|---|
| NAPA, CITY OF | 84,804 | 3 | Health |
| BERRYESSA HIGHLANDS | 715 | 38 | Health |
| CIRCLE OAKS WATER DISTRICT | 500 | 0 | Clean |
| BERRYESSA ESTATES (LBRID) | 474 | 12 | Health |
| BERRYESSA PINES WATER SYSTEM | 261 | 3 | Health |
| MEYERS WATER CO. | 250 | 2 | Health |
| HESS WINERY | 250 | 1 | Health |
| SPANISH FLAT WATER DISTRICT | 230 | 1 | Health |
| NAPA RIVER RANCH | 70 | 3 | Health |
| RIVER RANCH FARM WORKER CENTER | 66 | 0 | Clean |
| MONDAVI FARM WORKER CENTER | 66 | 0 | Clean |
| CALISTOGA FARM WORKER CENTER | 65 | 0 | Clean |
| EDDY DRIVE | 48 | 0 | Clean |
| MILTON ROAD WATER COMPANY | 44 | 7 | Health |
| BUCKTAIL MUTUAL WATER COMPANY | 42 | 1 | Health |
| R RANCH AT THE LAKE | 28 | 1 | Health |
Does this city have health-based water violations?
These health-based records can represent Maximum Contaminant Level (MCL), Treatment Technique (TT), or Maximum Residual Disinfectant Level (MRDL) categories. A historical record does not establish that water is currently unsafe.
| Water system | Contaminant | Begin Date |
|---|---|---|
| BUCKTAIL MUTUAL WATER COMPANY | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| SPANISH FLAT WATER DISTRICT | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| BERRYESSA PINES WATER SYSTEM | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| MILTON ROAD WATER COMPANY | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| HESS WINERY | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| R RANCH AT THE LAKE | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| NAPA RIVER RANCH | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| NAPA RIVER RANCH | Revised Total Coliform Rule | 2022-12-01 |
| NAPA RIVER RANCH | Revised Total Coliform Rule | 2022-12-01 |
| MEYERS WATER CO. | Selenium | 2021-07-01 |
| MEYERS WATER CO. | Selenium | 2021-07-01 |
| BERRYESSA HIGHLANDS | TTHM | 2020-04-01 |
| BERRYESSA HIGHLANDS | TTHM | 2020-04-01 |
| BERRYESSA ESTATES (LBRID) | TTHM | 2020-04-01 |
| BERRYESSA ESTATES (LBRID) | TTHM | 2020-04-01 |
| BERRYESSA HIGHLANDS | TTHM | 2020-01-01 |
| BERRYESSA HIGHLANDS | TTHM | 2020-01-01 |
| BERRYESSA ESTATES (LBRID) | TTHM | 2020-01-01 |
| BERRYESSA ESTATES (LBRID) | TTHM | 2020-01-01 |
| BERRYESSA HIGHLANDS | TTHM | 2019-10-01 |
| BERRYESSA HIGHLANDS | TTHM | 2019-10-01 |
| BERRYESSA ESTATES (LBRID) | TTHM | 2019-10-01 |
| BERRYESSA ESTATES (LBRID) | TTHM | 2019-10-01 |
| BERRYESSA HIGHLANDS | TTHM | 2019-07-01 |
| BERRYESSA HIGHLANDS | TTHM | 2019-07-01 |
| BERRYESSA ESTATES (LBRID) | TTHM | 2019-07-01 |
| BERRYESSA ESTATES (LBRID) | TTHM | 2019-07-01 |
| BERRYESSA HIGHLANDS | TTHM | 2019-04-01 |
| BERRYESSA HIGHLANDS | TTHM | 2019-04-01 |
| BERRYESSA HIGHLANDS | TTHM | 2019-01-01 |
| BERRYESSA HIGHLANDS | TTHM | 2019-01-01 |
| BERRYESSA HIGHLANDS | TTHM | 2018-10-01 |
| BERRYESSA HIGHLANDS | TTHM | 2018-10-01 |
| BERRYESSA HIGHLANDS | TTHM | 2018-07-01 |
| BERRYESSA HIGHLANDS | TTHM | 2018-07-01 |
| BERRYESSA HIGHLANDS | TTHM | 2018-04-01 |
| BERRYESSA HIGHLANDS | TTHM | 2018-04-01 |
| BERRYESSA HIGHLANDS | TTHM | 2018-01-01 |
| BERRYESSA HIGHLANDS | TTHM | 2018-01-01 |
| BERRYESSA HIGHLANDS | TTHM | 2017-10-01 |
| BERRYESSA HIGHLANDS | TTHM | 2017-10-01 |
| BERRYESSA HIGHLANDS | TTHM | 2017-07-01 |
| BERRYESSA HIGHLANDS | TTHM | 2017-07-01 |
| BERRYESSA HIGHLANDS | TTHM | 2017-04-01 |
| BERRYESSA HIGHLANDS | TTHM | 2017-04-01 |
| BERRYESSA HIGHLANDS | TTHM | 2017-01-01 |
| BERRYESSA HIGHLANDS | TTHM | 2017-01-01 |
| BERRYESSA HIGHLANDS | TTHM | 2016-10-01 |
| BERRYESSA HIGHLANDS | TTHM | 2016-10-01 |
| BERRYESSA HIGHLANDS | TTHM | 2016-07-01 |
What are Napa's health-based records for?
Napa's health-based violation records carry 6 distinct EPA codes: some name a substance, others the drinking-water rule that was breached. Counts are records on file in the EPA SDWIS extract, not current test results.
| Contaminant | Records | Systems |
|---|---|---|
| Tthm | 51 | 3 |
| Lead and Copper Rule Revisions | 7 | 7 |
| Coliform (TCR) | 6 | 1 |
| Total Haloacetic Acids (HAA5) | 4 | 2 |
| Selenium | 2 | 1 |
| Revised Total Coliform Rule | 2 | 1 |
TRI Facilities in Napa
| Facility | Total Releases |
|---|---|
| Vulcan Materials Co Napa Quarry | 1 lbs |
| Cmc Rebar - Ca - Napa | 0 lbs |
Frequently Asked Questions
What does EPA SDWIS list for drinking water in Napa, California? ▼
How many water violations does Napa have in this EPA extract? ▼
What contaminants were found in Napa water? ▼
How many water systems serve Napa? ▼
Where does Napa get its drinking water? ▼
Are there pollution sources near Napa? ▼
How does Napa compare in California?
Of the 909 California places with at least one community water system on file, Napa ranks #24 by number of systems (16).
Either side of it: Los Gatos (16), Modesto (16), Rosemead (15), San Diego (15)
About This Data
Figures here are the current EPA SDWIS extract joined to the 16 community water systems whose service area lists Napa, ranked against the 909 California places with at least one system on file. Data current as of 2026-08-25.
Water system data comes from the EPA's Safe Drinking Water Information System (SDWIS). PlainEnviro's violation fetch is restricted upstream to records EPA flags as health-based and then joined to active community water systems. Monitoring and reporting violations are not included.
A health-based violation row in this extract is a historical EPA registry entry. It does not describe water delivered today or current compliance status. Many records are later resolved, and public water systems notify customers when required. For current conditions, contact your local water utility or the state drinking water program.
TRI facility data comes from the EPA Toxic Release Inventory. Facilities shown are those that self-report to the TRI program. PlainEnviro presents this data without advocacy framing.
Read our methodology - how this data is sourced, computed, and verified.