Public water system · CA4901341
ActiveMolino Corner Water System
At a glance
Molino Corner Water System (PWSID CA4901341) is an active transient non-community water system in Sonoma County, California. It reports serving 100 people through 2 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 2 violations for this system; none is health-based, and the most recent began in August 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
100
Service connections
2
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Molino Corner Water System compare with other water systems in Sonoma County?
By EPA's size categories, Molino Corner Water System 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 Molino Corner Water System is about 31% 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 Molino Corner Water System?
EPA lists Molino Corner Water System 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 Molino Corner Water System have drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in August 2020. The violations listed here began between January 2019 and August 2020. By type: 1 monitoring and 1 monitoring and reporting. The contaminants or rules involved are Revised Total Coliform Rule and Nitrate. EPA lists 1 as resolved and 1 as archived. 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2020-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
All 2 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.
Molino Corner Water System: frequently asked questions
Who runs Molino Corner Water System?
Molino Corner Water System (PWSID CA4901341) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Molino Corner Water System serve?
Molino Corner Water System reports serving 100 people through 2 service connections in Sonoma County, California.
Where does Molino Corner Water System 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 Molino Corner Water System have any drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in August 2020. 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 Molino Corner Water System'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 2 violations for this system; none is health-based, and the most recent began in August 2020. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Molino Corner Water System's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Molino Corner Water System 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, “Molino Corner Water System, PWSID CA4901341, California”, https://aquacensus.com/water-systems/california/molino-corner-water-system-ca4901341 (data as of October 1, 2026).