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Public water system · CA1910034

Active

Downey - City, Water Dept.

At a glance

Downey - City, Water Dept. (PWSID CA1910034) is an active community water system in Los Angeles County, California. It reports serving 110,556 people through 23,459 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 5 violations for this system; 3 are health-based, and the most recent began in February 2018.

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

Population served

110,556

Service connections

23,459

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDCA1910034
System typeCommunity water system
Activity statusActive
Population served110,556
Service connections23,459
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyCA state drinking water program
City servedDowney
StateCalifornia
ZIP—
CountyLos Angeles County

How does Downey - City, Water Dept. compare with other water systems in Los Angeles County?

By EPA's size categories, Downey - City, Water Dept. is a very large system (more than 100,000 people). Los Angeles County has 275 active public water systems. Its population served is about 3 times the county average of 36,762 people per system, and accounts for 1.1% 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 Downey - City, Water Dept. is about 16 times 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 Downey - City, Water Dept.?

EPA lists Downey - City, Water Dept. as owned by a local government. 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. 100 of the 275 active systems in Los Angeles County (36%) are also owned by a local government.

Does Downey - City, Water Dept. have drinking water violations?

EPA's records list 5 violations for this system; 3 are health-based, and the most recent began in February 2018. The violations listed here began between August 2003 and February 2018. By type: 2 monitoring and reporting, 2 contaminant level above the legal limit and 1 required treatment not met. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 5 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.

BeganViolationContaminant or ruleHealth-basedStatus
2018-02-01Required treatment not metTreatment Technique, Level 2 Assessment (RTCR) · code 2BRevised Total Coliform Rulecode 8000YesResolved
2013-09-01Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25Total coliform bacteria (TCR)code 3100NoResolved
2012-05-24Monitoring and reportingMonitoring, Source Water (GWR) · code 34E. colicode 3014NoResolved
2008-09-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2003-08-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved

All 5 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.

Downey - City, Water Dept.: frequently asked questions

Who runs Downey - City, Water Dept.?

Downey - City, Water Dept. (PWSID CA1910034) is a community water system owned by a local government. It is regulated by the CA state drinking water program.

How many people does Downey - City, Water Dept. serve?

Downey - City, Water Dept. reports serving 110,556 people through 23,459 service connections in Los Angeles County, California.

Where does Downey - City, Water Dept. 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 Downey - City, Water Dept. have any drinking water violations?

EPA's records list 5 violations for this system; 3 are health-based, and the most recent began in February 2018. 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 Downey - City, Water Dept.'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 5 violations for this system; 3 are health-based, and the most recent began in February 2018. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.

Where can I find Downey - City, Water Dept.'s water quality report?

As a community water system, Downey - City, Water Dept. 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, “Downey - City, Water Dept., PWSID CA1910034, California”, https://aquacensus.com/water-systems/california/downey-city-water-dept-ca1910034 (data as of October 1, 2026).