Public water system · CA2801052
ActivePromontory Winery
At a glance
Promontory Winery (PWSID CA2801052) is an active transient non-community water system in Napa County, California. It reports serving 25 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 7 violations for this system; 3 are health-based, and the most recent began in October 2015.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
25
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Promontory Winery compare with other water systems in Napa County?
By EPA's size categories, Promontory 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 transient non-community water system reports serving 144 people, so Promontory Winery is well below that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. California has 3,016 active transient non-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 Promontory Winery?
EPA lists Promontory 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 Promontory Winery have drinking water violations?
EPA's records list 7 violations for this system; 3 are health-based, and the most recent began in October 2015. The violations listed here began between October 1999 and October 2015. By type: 4 monitoring and reporting and 3 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 of them). EPA lists 7 as resolved. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2015-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2013-07-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2001-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2000-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1999-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 7 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.
Promontory Winery: frequently asked questions
Who runs Promontory Winery?
Promontory Winery (PWSID CA2801052) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Promontory Winery serve?
Promontory Winery reports serving 25 people through 1 service connection in Napa County, California.
Where does Promontory 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 Promontory Winery have any drinking water violations?
EPA's records list 7 violations for this system; 3 are health-based, and the most recent began in October 2015. 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 Promontory 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. EPA's records list 7 violations for this system; 3 are health-based, and the most recent began in October 2015. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Promontory Winery's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Promontory Winery is a 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 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, “Promontory Winery, PWSID CA2801052, California”, https://aquacensus.com/water-systems/california/promontory-winery-ca2801052 (data as of October 1, 2026).