Public water system · CA1500374
ActiveCws-Grand Oaks Water System
At a glance
Cws-Grand Oaks Water System (PWSID CA1500374) is an active community water system in Kern County, California. It reports serving 122 people through 46 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 9 violations for this system; 2 are health-based, and the most recent began in November 1996.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
122
Service connections
46
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Cws-Grand Oaks Water System compare with other water systems in Kern County?
By EPA's size categories, Cws-Grand Oaks Water System is a very small system (500 people or fewer). Kern County has 327 active public water systems. Its population served is well below the county average of 3,140 people per system, and accounts for less than 0.1% of the 1,026,649 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active community water system reports serving 6,703 people, so Cws-Grand Oaks Water System is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. California has 2,997 active 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 Cws-Grand Oaks Water System?
EPA lists Cws-Grand Oaks 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. 263 of the 327 active systems in Kern County (80%) are also privately owned.
Does Cws-Grand Oaks Water System have drinking water violations?
EPA's records list 9 violations for this system; 2 are health-based, and the most recent began in November 1996. The violations listed here began between October 1980 and November 1996. By type: 4 monitoring and reporting, 3 public notice, recordkeeping or other and 2 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 5 as archived and 4 as resolved. 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. 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 |
|---|---|---|---|---|
| 1996-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1996-03-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1993-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1993-07-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1984-08-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | Archived |
| 1984-07-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | Archived |
| 1983-03-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | Archived |
| 1981-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Archived |
| 1980-10-30 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Archived |
All 9 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.
Cws-Grand Oaks Water System: frequently asked questions
Who runs Cws-Grand Oaks Water System?
Cws-Grand Oaks Water System (PWSID CA1500374) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Cws-Grand Oaks Water System serve?
Cws-Grand Oaks Water System reports serving 122 people through 46 service connections in Kern County, California.
Where does Cws-Grand Oaks 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 Cws-Grand Oaks Water System have any drinking water violations?
EPA's records list 9 violations for this system; 2 are health-based, and the most recent began in November 1996. 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 Cws-Grand Oaks 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 9 violations for this system; 2 are health-based, and the most recent began in November 1996. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Cws-Grand Oaks Water System's water quality report?
As a community water system, Cws-Grand Oaks Water System must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Kern County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Cws - Bakersfield | Kern | 267,881 | Community | Surface water |
| Bakersfield, City of | Kern | 160,144 | Community | Purchased surface water |
| Delano, City of | Kern | 51,428 | Community | Groundwater |
| Oildale Mwc | Kern | 44,899 | Community | Purchased surface water |
| Indian Wells Valley W.D. | Kern | 41,580 | Community | Groundwater |
| Tejon Castac Wd - I5 & Laval Rd | Kern | 38,125 | Community | 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, “Cws-Grand Oaks Water System, PWSID CA1500374, California”, https://aquacensus.com/water-systems/california/cws-grand-oaks-water-system-ca1500374 (data as of October 1, 2026).