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Public water system · CA1900303

Active

Llano Mutual Water Company

At a glance

Llano Mutual Water Company (PWSID CA1900303) is an active community water system in Los Angeles County, California. It reports serving 245 people through 83 service connections. Its primary water source is purchased groundwater, and EPA lists it as privately owned. EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in October 2024.

Dataset updated . Source: EPA SDWIS/ECHO public records.

Population served

245

Service connections

83

Primary source

GWP

Purchased groundwater

System type

CWS

Community water system

System record

PWSIDCA1900303
System typeCommunity water system
Activity statusActive
Population served245
Service connections83
Primary water sourcePurchased groundwater
Owner typePrivate
Primacy agencyCA state drinking water program
City served—
StateCalifornia
ZIP—
CountyLos Angeles County

How does Llano Mutual Water Company compare with other water systems in Los Angeles County?

By EPA's size categories, Llano Mutual Water Company is a very small system (500 people or fewer). 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 Llano Mutual Water Company 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 groundwater means the system buys groundwater from another public water system rather than drawing its own. 76 California systems (1%) list purchased groundwater as their primary source.

Who owns and regulates Llano Mutual Water Company?

EPA lists Llano Mutual Water Company 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 Llano Mutual Water Company have drinking water violations?

EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in October 2024. The violations listed here began between January 2011 and October 2024. By type: 6 monitoring and reporting, 1 required treatment not met and 1 reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (6 of them). EPA lists 6 as resolved and 2 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.

BeganViolationContaminant or ruleHealth-basedStatus
2024-10-17Required treatment not metLSL Inventory · code 2ELead and Copper Rule Revisionscode 5200YesUnaddressed
2024-10-17ReportingLSL Reporting · code 4GLead and Copper Rule Revisionscode 5200NoUnaddressed
2011-10-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2011-09-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2011-08-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2011-07-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2011-02-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2011-01-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved

All 8 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.

Llano Mutual Water Company: frequently asked questions

Who runs Llano Mutual Water Company?

Llano Mutual Water Company (PWSID CA1900303) is a community water system privately owned. It is regulated by the CA state drinking water program.

How many people does Llano Mutual Water Company serve?

Llano Mutual Water Company reports serving 245 people through 83 service connections in Los Angeles County, California.

Where does Llano Mutual Water Company get its water?

EPA SDWIS lists this system's primary water source as purchased groundwater. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own.

Does Llano Mutual Water Company have any drinking water violations?

EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in October 2024. 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 Llano Mutual Water Company'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 8 violations for this system; 1 is health-based, and the most recent began in October 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.

Where can I find Llano Mutual Water Company's water quality report?

As a community water system, Llano Mutual Water Company 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 systemCountyPopulation servedTypeSource
Los Angeles-City, Dept. of Water & PowerLos Angeles3,875,566CommunitySurface water
Long Beach Utilities DepartmentLos Angeles466,772CommunityPurchased surface water
Santa Clarita Valley Water AgencyLos Angeles294,090CommunitySurface water
Gswc - SouthwestLos Angeles277,740CommunityPurchased surface water
San Gabriel Valley Water Co.-El MonteLos Angeles248,000CommunityGroundwater
Los Angeles Cwwd 40 Reg 4 & 34 LancasterLos Angeles208,129CommunityPurchased 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, “Llano Mutual Water Company, PWSID CA1900303, California”, https://aquacensus.com/water-systems/california/llano-mutual-water-company-ca1900303 (data as of October 1, 2026).