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Public water system · CA2801046

Active

St. Supery Winery

At a glance

St. Supery Winery (PWSID CA2801046) is an active non-transient non-community water system in Napa County, California. It reports serving 40 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in July 2017.

Dataset updated . Source: EPA SDWIS/ECHO public records.

Population served

40

Service connections

1

Primary source

GW

Groundwater

System type

NTNCWS

Non-transient non-community water system

System record

PWSIDCA2801046
System typeNon-transient non-community water system
Activity statusActive
Population served40
Service connections1
Primary water sourceGroundwater
Owner typePrivate
Primacy agencyCA state drinking water program
City served—
StateCalifornia
ZIP—
CountyNapa County

How does St. Supery Winery compare with other water systems in Napa County?

By EPA's size categories, St. Supery Winery 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 non-transient non-community water system reports serving 430 people, so St. Supery Winery is well below that figure.

What does “non-transient non-community water system” mean?

A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. California has 1,466 active non-transient non-community water systems, 20% 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 St. Supery Winery?

EPA lists St. Supery Winery 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 St. Supery Winery have drinking water violations?

Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in July 2017. The violations listed here began between June 1998 and July 2017. By type: 8 monitoring and reporting, 3 contaminant level above the legal limit and 1 monitoring. The contaminant or rule involved most often is Total coliform bacteria (TCR) (11 of them). EPA lists 11 as resolved 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. 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.

BeganViolationContaminant or ruleHealth-basedStatus
2017-07-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2014-03-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2014-02-01Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25Total coliform bacteria (TCR)code 3100NoResolved
2008-12-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2007-10-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2006-01-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2005-01-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2001-08-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2000-06-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
1999-05-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
1999-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
1998-06-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoArchived

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.

St. Supery Winery: frequently asked questions

Who runs St. Supery Winery?

St. Supery Winery (PWSID CA2801046) is a non-transient non-community water system privately owned. It is regulated by the CA state drinking water program.

How many people does St. Supery Winery serve?

St. Supery Winery reports serving 40 people through 1 service connection in Napa County, California.

Where does St. Supery Winery 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 St. Supery Winery have any drinking water violations?

Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in July 2017. 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 St. Supery Winery'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, 3 are health-based, and the most recent began in July 2017. For current results, consult EPA ECHO, or the CA state drinking water program.

Where can I find St. Supery Winery's water quality report?

The annual Consumer Confidence Report requirement applies to community water systems. St. Supery Winery is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.

Other water systems in Napa County

Water systemCountyPopulation servedTypeSource
Napa, City ofNapa84,804CommunitySurface water
American Canyon, City ofNapa21,437CommunitySurface water
Phelps VineyardsNapa19,412Non-transient non-communityGroundwater
Calistoga, City ofNapa5,610CommunitySurface water
St. Helena, City ofNapa5,386CommunitySurface water
Town of YountvilleNapa2,787CommunityPurchased 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, “St. Supery Winery, PWSID CA2801046, California”, https://aquacensus.com/water-systems/california/st-supery-winery-ca2801046 (data as of October 1, 2026).