Public water system · CA2300858
ActiveBlack Oak Facility
At a glance
Black Oak Facility (PWSID CA2300858) is an active transient non-community water system in Mendocino County, California. It reports serving 200 people through 3 service connections. Its primary water source is surface water, and EPA lists it as privately owned. EPA's records list 6 violations for this system; 2 are health-based, and the most recent began in August 2019.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
200
Service connections
3
Primary source
SW
Surface water
System type
TNCWS
Transient non-community water system
System record
How does Black Oak Facility compare with other water systems in Mendocino County?
By EPA's size categories, Black Oak Facility is a very small system (500 people or fewer). Mendocino County has 144 active public water systems. Its population served is about 65% below the county average of 576 people per system, and accounts for 0.2% of the 82,868 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 Black Oak Facility is about 39% above 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. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 609 California systems (8.1%) list surface water as their primary source.
Who owns and regulates Black Oak Facility?
EPA lists Black Oak Facility 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. 98 of the 144 active systems in Mendocino County (68%) are also privately owned.
Does Black Oak Facility have drinking water violations?
EPA's records list 6 violations for this system; 2 are health-based, and the most recent began in August 2019. The violations listed here began between June 1999 and August 2019. By type: 3 monitoring and reporting, 2 required treatment not met and 1 monitoring. The contaminant or rule involved most often is Surface Water Treatment Rule (4 of them). EPA lists 6 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 |
|---|---|---|---|---|
| 2019-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2009-05-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2006-08-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2006-08-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2005-05-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 1999-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 6 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.
Black Oak Facility: frequently asked questions
Who runs Black Oak Facility?
Black Oak Facility (PWSID CA2300858) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Black Oak Facility serve?
Black Oak Facility reports serving 200 people through 3 service connections in Mendocino County, California.
Where does Black Oak Facility get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Black Oak Facility have any drinking water violations?
EPA's records list 6 violations for this system; 2 are health-based, and the most recent began in August 2019. 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 Black Oak Facility'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 6 violations for this system; 2 are health-based, and the most recent began in August 2019. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Black Oak Facility's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Black Oak Facility 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 Mendocino County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Ukiah, City of | Mendocino | 16,607 | Community | Surface water |
| Fort Bragg, City of | Mendocino | 6,919 | Community | Surface water |
| Willits, City of | Mendocino | 6,175 | Community | Surface water |
| Millview County Water District | Mendocino | 5,500 | Community | Surface water |
| Redwood Valley County Water District | Mendocino | 5,200 | Community | Surface water |
| Willow County Water District | Mendocino | 3,797 | Community | Purchased surface water |
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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, “Black Oak Facility, PWSID CA2300858, California”, https://aquacensus.com/water-systems/california/black-oak-facility-ca2300858 (data as of October 1, 2026).