Public water system · CA4901274
ActiveNicholson Ranch Winery
At a glance
Nicholson Ranch Winery (PWSID CA4901274) is an active transient non-community water system in Sonoma County, California. It reports serving 150 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 4 violations for this system; none is health-based, and the most recent began in March 2007.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
150
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Nicholson Ranch Winery compare with other water systems in Sonoma County?
By EPA's size categories, Nicholson Ranch 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 transient non-community water system reports serving 144 people, so Nicholson Ranch Winery is roughly in line with 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 Nicholson Ranch Winery?
EPA lists Nicholson Ranch 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 Nicholson Ranch Winery have drinking water violations?
EPA's records list 4 violations for this system; none is health-based, and the most recent began in March 2007. The violations listed here began between September 2004 and March 2007. By type: 4 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 4 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 |
|---|---|---|---|---|
| 2007-03-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2004-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 4 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.
Nicholson Ranch Winery: frequently asked questions
Who runs Nicholson Ranch Winery?
Nicholson Ranch Winery (PWSID CA4901274) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Nicholson Ranch Winery serve?
Nicholson Ranch Winery reports serving 150 people through 1 service connection in Sonoma County, California.
Where does Nicholson Ranch 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 Nicholson Ranch Winery have any drinking water violations?
EPA's records list 4 violations for this system; none is health-based, and the most recent began in March 2007. 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 Nicholson Ranch 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 4 violations for this system; none is health-based, and the most recent began in March 2007. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Nicholson Ranch Winery's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Nicholson Ranch 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 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, “Nicholson Ranch Winery, PWSID CA4901274, California”, https://aquacensus.com/water-systems/california/nicholson-ranch-winery-ca4901274 (data as of October 1, 2026).