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Public water system · CA4901060

Active

Duncans Mills Camping Club

At a glance

Duncans Mills Camping Club (PWSID CA4901060) is an active transient non-community water system in Sonoma County, California. It reports serving 127 people through 125 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in March 2016.

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

Population served

127

Service connections

125

Primary source

GW

Groundwater

System type

TNCWS

Transient non-community water system

System record

PWSIDCA4901060
System typeTransient non-community water system
Activity statusActive
Population served127
Service connections125
Primary water sourceGroundwater
Owner typePrivate
Primacy agencyCA state drinking water program
City served—
StateCalifornia
ZIP—
CountySonoma County

How does Duncans Mills Camping Club compare with other water systems in Sonoma County?

By EPA's size categories, Duncans Mills Camping Club 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 Duncans Mills Camping Club is about 12% 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 Duncans Mills Camping Club?

EPA lists Duncans Mills Camping Club 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 Duncans Mills Camping Club have drinking water violations?

EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in March 2016. The violations listed here began between October 1995 and March 2016. By type: 2 monitoring and reporting, 1 contaminant level above the legal limit and 1 public notice, recordkeeping or other. 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.

BeganViolationContaminant or ruleHealth-basedStatus
2016-03-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21Total coliform bacteria (TCR)code 3100YesResolved
2012-08-27Public notice, recordkeeping or otherPublic Notification Violation without NPDWR Violation · code 76Public Noticecode 7500NoResolved
2012-06-01Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26Total coliform bacteria (TCR)code 3100NoResolved
1995-10-01Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25Total coliform bacteria (TCR)code 3100NoResolved

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.

Duncans Mills Camping Club: frequently asked questions

Who runs Duncans Mills Camping Club?

Duncans Mills Camping Club (PWSID CA4901060) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.

How many people does Duncans Mills Camping Club serve?

Duncans Mills Camping Club reports serving 127 people through 125 service connections in Sonoma County, California.

Where does Duncans Mills Camping Club 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 Duncans Mills Camping Club have any drinking water violations?

EPA's records list 4 violations for this system; 1 is health-based, and the most recent began in March 2016. 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 Duncans Mills Camping Club'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; 1 is health-based, and the most recent began in March 2016. For current results, consult EPA ECHO, or the CA state drinking water program.

Where can I find Duncans Mills Camping Club's water quality report?

The annual Consumer Confidence Report requirement applies to community water systems. Duncans Mills Camping Club 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 systemCountyPopulation servedTypeSource
Santa Rosa, City ofSonoma175,396CommunityGroundwater
Petaluma, City ofSonoma60,781CommunityGroundwater
Rohnert Park, City ofSonoma43,821CommunityGroundwater
Windsor, Town ofSonoma25,561CommunityGroundwater
Valley of the Moon Water DistrictSonoma23,107CommunityGroundwater
Sonoma, City ofSonoma11,725CommunityGroundwater

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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, “Duncans Mills Camping Club, PWSID CA4901060, California”, https://aquacensus.com/water-systems/california/duncans-mills-camping-club-ca4901060 (data as of October 1, 2026).