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Public water system · CA4901248

Active

Matanzas Creek Winery

At a glance

Matanzas Creek Winery (PWSID CA4901248) is an active non-transient non-community water system in Sonoma County, California. It reports serving 139 people through 7 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 10 violations for this system; 5 are health-based, and the most recent began in April 2015.

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

Population served

139

Service connections

7

Primary source

GW

Groundwater

System type

NTNCWS

Non-transient non-community water system

System record

PWSIDCA4901248
System typeNon-transient non-community water system
Activity statusActive
Population served139
Service connections7
Primary water sourceGroundwater
Owner typePrivate
Primacy agencyCA state drinking water program
City served—
StateCalifornia
ZIP—
CountySonoma County

How does Matanzas Creek Winery compare with other water systems in Sonoma County?

By EPA's size categories, Matanzas Creek 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 Matanzas Creek 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 Matanzas Creek Winery?

EPA lists Matanzas Creek 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 Matanzas Creek Winery have drinking water violations?

EPA's records list 10 violations for this system; 5 are health-based, and the most recent began in April 2015. The violations listed here began between November 1999 and April 2015. By type: 5 contaminant level above the legal limit and 5 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (9 of them). EPA lists 10 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
2015-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2008-11-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2008-10-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21Total coliform bacteria (TCR)code 3100YesResolved
2008-06-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2008-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21Total coliform bacteria (TCR)code 3100YesResolved
2007-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved
2003-07-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2003-06-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2001-12-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
1999-11-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved

All 10 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.

Matanzas Creek Winery: frequently asked questions

Who runs Matanzas Creek Winery?

Matanzas Creek Winery (PWSID CA4901248) is a non-transient non-community water system privately owned. It is regulated by the CA state drinking water program.

How many people does Matanzas Creek Winery serve?

Matanzas Creek Winery reports serving 139 people through 7 service connections in Sonoma County, California.

Where does Matanzas Creek 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 Matanzas Creek Winery have any drinking water violations?

EPA's records list 10 violations for this system; 5 are health-based, and the most recent began in April 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 Matanzas Creek 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 10 violations for this system; 5 are health-based, and the most recent began in April 2015. For current results, consult EPA ECHO, or the CA state drinking water program.

Where can I find Matanzas Creek Winery's water quality report?

The annual Consumer Confidence Report requirement applies to community water systems. Matanzas Creek 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 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, “Matanzas Creek Winery, PWSID CA4901248, California”, https://aquacensus.com/water-systems/california/matanzas-creek-winery-ca4901248 (data as of October 1, 2026).