Public water system · CA5000109
ActiveCeres Unified/Westport School
At a glance
Ceres Unified/Westport School (PWSID CA5000109) is an active non-transient non-community water system in Stanislaus County, California. It reports serving 450 people through 6 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 12 are health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
450
Service connections
6
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Ceres Unified/Westport School compare with other water systems in Stanislaus County?
By EPA's size categories, Ceres Unified/Westport School is a very small system (500 people or fewer). Stanislaus County has 191 active public water systems. Its population served is well below the county average of 2,684 people per system, and accounts for less than 0.1% 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 non-transient non-community water system reports serving 430 people, so Ceres Unified/Westport School is roughly in line with that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. California has 1,466 active non-transient non-community water systems, 20% 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 Ceres Unified/Westport School?
EPA lists Ceres Unified/Westport School 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 Ceres Unified/Westport School have drinking water violations?
Of the 12 most recent violations in EPA's records, 12 are health-based, and the most recent began in January 2026. The violations listed here began between October 2024 and January 2026. By type: 12 contaminant level above the legal limit. The contaminant or rule involved most often is Combined Uranium (6 of them). EPA lists 12 as archived. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2026-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Uraniumcode 4006 | Yes | Archived |
| 2026-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2025-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2025-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Uraniumcode 4006 | Yes | Archived |
| 2025-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2025-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Uraniumcode 4006 | Yes | Archived |
| 2025-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Uraniumcode 4006 | Yes | Archived |
| 2025-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2025-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Uraniumcode 4006 | Yes | Archived |
| 2025-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2024-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
| 2024-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Uraniumcode 4006 | Yes | Archived |
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.
Ceres Unified/Westport School: frequently asked questions
Who runs Ceres Unified/Westport School?
Ceres Unified/Westport School (PWSID CA5000109) is a non-transient non-community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Ceres Unified/Westport School serve?
Ceres Unified/Westport School reports serving 450 people through 6 service connections in Stanislaus County, California.
Where does Ceres Unified/Westport School 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 Ceres Unified/Westport School have any drinking water violations?
Of the 12 most recent violations in EPA's records, 12 are health-based, and the most recent began in January 2026. 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 Ceres Unified/Westport School'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. Of the 12 most recent violations in EPA's records, 12 are health-based, and the most recent began in January 2026. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Ceres Unified/Westport School's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Ceres Unified/Westport School is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in Stanislaus County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Modesto, City of | Stanislaus | 218,771 | Community | Purchased surface water |
| Turlock, City of | Stanislaus | 72,682 | Community | Purchased surface water |
| Ceres, City of | Stanislaus | 54,513 | Community | Purchased surface water |
| Patterson, City of | Stanislaus | 24,977 | Community | Groundwater |
| Riverbank, City of | Stanislaus | 24,834 | Community | Groundwater |
| Oakdale, City of | Stanislaus | 23,235 | Community | Groundwater |
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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 Unified/Westport School, PWSID CA5000109, California”, https://aquacensus.com/water-systems/california/ceres-unified-westport-school-ca5000109 (data as of October 1, 2026).