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Public water system · CA5010028

Active

Ceres, City of

At a glance

City of Ceres (PWSID CA5010028) is an active community water system in Stanislaus County, California. It reports serving 54,513 people through 11,881 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in October 2024.

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

Population served

54,513

Service connections

11,881

Primary source

SWP

Purchased surface water

System type

CWS

Community water system

System record

PWSIDCA5010028
System typeCommunity water system
Activity statusActive
Population served54,513
Service connections11,881
Primary water sourcePurchased surface water
Owner typeLocal government
Primacy agencyCA state drinking water program
City servedCeres
StateCalifornia
ZIP—
CountyStanislaus County

How does City of Ceres compare with other water systems in Stanislaus County?

By EPA's size categories, City of Ceres is a large system (10,001 to 100,000 people). Stanislaus County has 191 active public water systems, and City of Ceres is the 3rd-largest of them by population served. Its population served is about 20 times the county average of 2,684 people per system, and accounts for 11% of the 512,656 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 City of Ceres is about 8.1 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. 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 City of Ceres?

EPA lists City of Ceres 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. 57 of the 191 active systems in Stanislaus County (30%) are also owned by a local government.

Does City of Ceres have drinking water violations?

Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in October 2024. The violations listed here began between April 1993 and October 2024. By type: 8 contaminant level above the legal limit, 2 monitoring and reporting, 1 required treatment not met and 1 reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 of them). EPA lists 10 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
2015-10-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Combined Uraniumcode 4006YesResolved
2010-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2009-06-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2007-07-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01Combined Uraniumcode 4006YesResolved
2007-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Nitratecode 1040YesResolved
2003-01-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2001-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
1995-03-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
1993-08-01Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24Total coliform bacteria (TCR)code 3100NoResolved
1993-04-01Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24Total coliform bacteria (TCR)code 3100NoResolved

The 12 most recent 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.

City of Ceres: frequently asked questions

Who runs City of Ceres?

City of Ceres (PWSID CA5010028) is a community water system owned by a local government. It is regulated by the CA state drinking water program.

How many people does City of Ceres serve?

City of Ceres reports serving 54,513 people through 11,881 service connections in Stanislaus County, California.

Where does City of Ceres 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 City of Ceres have any drinking water violations?

Of the 12 most recent violations in EPA's records, 9 are 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 City of Ceres' 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. Of the 12 most recent violations in EPA's records, 9 are 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 City of Ceres' water quality report?

As a community water system, City of Ceres 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 Stanislaus County

Water systemCountyPopulation servedTypeSource
Modesto, City ofStanislaus218,771CommunityPurchased surface water
Turlock, City ofStanislaus72,682CommunityPurchased surface water
Patterson, City ofStanislaus24,977CommunityGroundwater
Riverbank, City ofStanislaus24,834CommunityGroundwater
Oakdale, City ofStanislaus23,235CommunityGroundwater
City of Modesto - SalidaStanislaus14,537CommunityPurchased 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, “Ceres, City of, PWSID CA5010028, California”, https://aquacensus.com/water-systems/california/ceres-city-of-ca5010028 (data as of October 1, 2026).