Public water system · CA1910243
ActiveCalifornia Water Service Co-Leona Valley
At a glance
California Water Service Co-Leona Valley (PWSID CA1910243) is an active community water system in Los Angeles County, California. It reports serving 878 people through 430 service connections. Its primary water source is purchased surface water, and EPA lists it as privately owned. EPA's records list one violation for this system; it is health-based, and the most recent began in April 1993.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
878
Service connections
430
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does California Water Service Co-Leona Valley compare with other water systems in Los Angeles County?
By EPA's size categories, California Water Service Co-Leona Valley is a small system (501 to 3,300 people). Los Angeles County has 275 active public water systems. Its population served is well below the county average of 36,762 people per system, and accounts for less than 0.1% of the 10,109,668 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 California Water Service Co-Leona Valley 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 506 California systems (6.8%) list purchased surface water as their primary source.
Who owns and regulates California Water Service Co-Leona Valley?
EPA lists California Water Service Co-Leona Valley 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. 150 of the 275 active systems in Los Angeles County (55%) are also privately owned.
Does California Water Service Co-Leona Valley have drinking water violations?
EPA's records list one violation for this system; it is health-based, and the most recent began in April 1993. By type: 1 contaminant level above the legal limit. The contaminant or rule involved is Nitrate. EPA lists 1 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 |
|---|---|---|---|---|
| 1993-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Nitratecode 1040 | Yes | Resolved |
The one violation in EPA's records.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.
California Water Service Co-Leona Valley: frequently asked questions
Who runs California Water Service Co-Leona Valley?
California Water Service Co-Leona Valley (PWSID CA1910243) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does California Water Service Co-Leona Valley serve?
California Water Service Co-Leona Valley reports serving 878 people through 430 service connections in Los Angeles County, California.
Where does California Water Service Co-Leona Valley get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does California Water Service Co-Leona Valley have any drinking water violations?
EPA's records list one violation for this system; it is health-based, and the most recent began in April 1993. 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 California Water Service Co-Leona Valley'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 one violation for this system; it is health-based, and the most recent began in April 1993. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find California Water Service Co-Leona Valley's water quality report?
As a community water system, California Water Service Co-Leona Valley 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 Los Angeles County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Los Angeles-City, Dept. of Water & Power | Los Angeles | 3,875,566 | Community | Surface water |
| Long Beach Utilities Department | Los Angeles | 466,772 | Community | Purchased surface water |
| Santa Clarita Valley Water Agency | Los Angeles | 294,090 | Community | Surface water |
| Gswc - Southwest | Los Angeles | 277,740 | Community | Purchased surface water |
| San Gabriel Valley Water Co.-El Monte | Los Angeles | 248,000 | Community | Groundwater |
| Los Angeles Cwwd 40 Reg 4 & 34 Lancaster | Los Angeles | 208,129 | 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, “California Water Service Co-Leona Valley, PWSID CA1910243, California”, https://aquacensus.com/water-systems/california/california-water-service-co-leona-valley-ca1910243 (data as of October 1, 2026).