Public water system · CA4901203
ActiveAsti Winery
At a glance
Asti Winery (PWSID CA4901203) is an active non-transient non-community water system in Sonoma County, California. It reports serving 67 people through 4 service connections. Its primary water source is groundwater under influence of surface water, and EPA lists it as privately owned. EPA's records list one violation for this system; it is not health-based, and the most recent began in February 2010.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
67
Service connections
4
Primary source
GU
Groundwater under influence of surface water
System type
NTNCWS
Non-transient non-community water system
System record
How does Asti Winery compare with other water systems in Sonoma County?
By EPA's size categories, Asti Winery is a very small system (500 people or fewer). Sonoma County has 441 active public water systems. Its population served is well below the county average of 1,092 people per system, and accounts for less than 0.1% of the 481,435 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 Asti 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 under the influence of surface water is well or spring water that the regulator has found to be affected by nearby surface water, so it is regulated under the surface-water treatment rules. 105 California systems (1.4%) list groundwater under influence of surface water as their primary source.
Who owns and regulates Asti Winery?
EPA lists Asti 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. 371 of the 441 active systems in Sonoma County (84%) are also privately owned.
Does Asti Winery have drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in February 2010. By type: 1 public notice, recordkeeping or other. The contaminant or rule involved is Groundwater Rule. EPA lists 1 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 |
|---|---|---|---|---|
| 2010-02-28 | Public notice, recordkeeping or otherFailure to Consult with State · code 20 | Groundwater Rulecode 0700 | No | Resolved |
The one violation in EPA's records.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.
Asti Winery: frequently asked questions
Who runs Asti Winery?
Asti Winery (PWSID CA4901203) is a non-transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Asti Winery serve?
Asti Winery reports serving 67 people through 4 service connections in Sonoma County, California.
Where does Asti Winery get its water?
EPA SDWIS lists this system's primary water source as groundwater under influence of surface water. Groundwater under the influence of surface water is well or spring water that the regulator has found to be affected by nearby surface water, so it is regulated under the surface-water treatment rules.
Does Asti Winery have any drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in February 2010. 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 Asti 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 one violation for this system; it is not health-based, and the most recent began in February 2010. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Asti Winery's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Asti 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 Sonoma County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Santa Rosa, City of | Sonoma | 175,396 | Community | Groundwater |
| Petaluma, City of | Sonoma | 60,781 | Community | Groundwater |
| Rohnert Park, City of | Sonoma | 43,821 | Community | Groundwater |
| Windsor, Town of | Sonoma | 25,561 | Community | Groundwater |
| Valley of the Moon Water District | Sonoma | 23,107 | Community | Groundwater |
| Sonoma, City of | Sonoma | 11,725 | Community | Groundwater |
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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, “Asti Winery, PWSID CA4901203, California”, https://aquacensus.com/water-systems/california/asti-winery-ca4901203 (data as of October 1, 2026).