Public water system · CA1000579
ActiveOak Knoll Professional Ctr
At a glance
Oak Knoll Professional Ctr (PWSID CA1000579) is an active transient non-community water system in Fresno County, California. It reports serving 25 people through 4 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 3 violations for this system; 1 is health-based, and the most recent began in December 2008.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
25
Service connections
4
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Oak Knoll Professional Ctr compare with other water systems in Fresno County?
By EPA's size categories, Oak Knoll Professional Ctr is a very small system (500 people or fewer). Fresno County has 328 active public water systems. Its population served is well below the county average of 3,205 people per system, and accounts for less than 0.1% of the 1,051,276 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 Oak Knoll Professional Ctr is well 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 Oak Knoll Professional Ctr?
EPA lists Oak Knoll Professional Ctr 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. 220 of the 328 active systems in Fresno County (67%) are also privately owned.
Does Oak Knoll Professional Ctr have drinking water violations?
EPA's records list 3 violations for this system; 1 is health-based, and the most recent began in December 2008. The violations listed here began between September 2008 and December 2008. By type: 2 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 3 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 |
|---|---|---|---|---|
| 2008-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-10-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-09-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 3 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.
Oak Knoll Professional Ctr: frequently asked questions
Who runs Oak Knoll Professional Ctr?
Oak Knoll Professional Ctr (PWSID CA1000579) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Oak Knoll Professional Ctr serve?
Oak Knoll Professional Ctr reports serving 25 people through 4 service connections in Fresno County, California.
Where does Oak Knoll Professional Ctr 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 Oak Knoll Professional Ctr have any drinking water violations?
EPA's records list 3 violations for this system; 1 is health-based, and the most recent began in December 2008. 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 Oak Knoll Professional Ctr'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 3 violations for this system; 1 is health-based, and the most recent began in December 2008. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Oak Knoll Professional Ctr's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Oak Knoll Professional Ctr 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 Fresno County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Fresno | Fresno | 545,716 | Community | Surface water |
| City of Clovis | Fresno | 130,130 | Community | Surface water |
| California State University Fresno | Fresno | 41,000 | Community | Groundwater |
| Cws - Selma | Fresno | 26,517 | Community | Groundwater |
| City of Sanger | Fresno | 26,357 | Community | Groundwater |
| Reedley, City of | Fresno | 26,076 | 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, “Oak Knoll Professional Ctr, PWSID CA1000579, California”, https://aquacensus.com/water-systems/california/oak-knoll-professional-ctr-ca1000579 (data as of October 1, 2026).