Public water system · CA2810013
ActiveBerryessa Highlands
At a glance
Berryessa Highlands (PWSID CA2810013) is an active community water system in Napa County, California. It reports serving 715 people through 256 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in August 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
715
Service connections
256
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Berryessa Highlands compare with other water systems in Napa County?
By EPA's size categories, Berryessa Highlands is a small system (501 to 3,300 people). Napa County has 188 active public water systems. Its population served is about 17% below the county average of 861 people per system, and accounts for 0.4% of the 161,950 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active community water system reports serving 6,703 people, so Berryessa Highlands is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. California has 2,997 active community water systems, 40% of the state's 7,479 active systems. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 609 California systems (8.1%) list surface water as their primary source.
Who owns and regulates Berryessa Highlands?
EPA lists Berryessa Highlands as owned by a local government. The CA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 15 of the 188 active systems in Napa County (8%) are also owned by a local government.
Does Berryessa Highlands have drinking water violations?
Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in August 2024. The violations listed here began between January 2018 and August 2024. By type: 10 contaminant level above the legal limit and 2 monitoring. The contaminant or rule involved most often is Total trihalomethanes (TTHM) (10 of them). EPA lists 10 as resolved and 2 as archived. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2024-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Archived |
| 2020-12-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Archived |
| 2020-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2020-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2019-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2019-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2019-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2019-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2018-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2018-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2018-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2018-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Berryessa Highlands: frequently asked questions
Who runs Berryessa Highlands?
Berryessa Highlands (PWSID CA2810013) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Berryessa Highlands serve?
Berryessa Highlands reports serving 715 people through 256 service connections in Napa County, California.
Where does Berryessa Highlands get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Berryessa Highlands have any drinking water violations?
Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in August 2024. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Berryessa Highlands' water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in August 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Berryessa Highlands' water quality report?
As a community water system, Berryessa Highlands must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Napa County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Napa, City of | Napa | 84,804 | Community | Surface water |
| American Canyon, City of | Napa | 21,437 | Community | Surface water |
| Phelps Vineyards | Napa | 19,412 | Non-transient non-community | Groundwater |
| Calistoga, City of | Napa | 5,610 | Community | Surface water |
| St. Helena, City of | Napa | 5,386 | Community | Surface water |
| Town of Yountville | Napa | 2,787 | Community | Purchased surface water |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Berryessa Highlands, PWSID CA2810013, California”, https://aquacensus.com/water-systems/california/berryessa-highlands-ca2810013 (data as of October 1, 2026).