Public water system · CA2800531
ActiveNapa River Ranch
At a glance
Napa River Ranch (PWSID CA2800531) is an active community water system in Napa County, California. It reports serving 70 people through 14 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
70
Service connections
14
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Napa River Ranch compare with other water systems in Napa County?
By EPA's size categories, Napa River Ranch is a very small system (500 people or fewer). Napa County has 188 active public water systems. Its population served is well below the county average of 861 people per system, and accounts for less than 0.1% 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 Napa River Ranch 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. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,179 California systems (83%) list groundwater as their primary source.
Who owns and regulates Napa River Ranch?
EPA lists Napa River Ranch as privately owned. 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. 168 of the 188 active systems in Napa County (89%) are also privately owned.
Does Napa River Ranch have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in January 2026. The violations listed here began between December 2022 and January 2026. By type: 6 monitoring and reporting, 2 public notice, recordkeeping or other, 2 reporting and 2 required treatment not met. The contaminant or rule involved most often is Lead and Copper Rule (4 of them). EPA lists 5 as resolved, 4 as addressed, 2 as unaddressed and 1 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. Addressed means the violation is not resolved or archived and is covered by formal enforcement. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement. 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 |
|---|---|---|---|---|
| 2026-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Addressed |
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Addressed |
| 2025-07-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Addressed |
| 2025-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 2025-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Addressed |
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Unaddressed |
| 2023-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2023-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2023-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2022-12-01 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-12-01 | Required treatment not metTreatment Technique, Level 1 Assessment (RTCR) · code 2A | Revised Total Coliform Rulecode 8000 | 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.
Napa River Ranch: frequently asked questions
Who runs Napa River Ranch?
Napa River Ranch (PWSID CA2800531) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Napa River Ranch serve?
Napa River Ranch reports serving 70 people through 14 service connections in Napa County, California.
Where does Napa River Ranch get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Napa River Ranch have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in January 2026. 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 Napa River Ranch's 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, 2 are health-based, and the most recent began in January 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Napa River Ranch's water quality report?
As a community water system, Napa River Ranch 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, “Napa River Ranch, PWSID CA2800531, California”, https://aquacensus.com/water-systems/california/napa-river-ranch-ca2800531 (data as of October 1, 2026).