Public water system · CA1300517
ActiveU.S. Gypsum Co
At a glance
U.S. Gypsum Co (PWSID CA1300517) is an active non-transient non-community water system in Imperial County, California. It reports serving 280 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
280
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does U.S. Gypsum Co compare with other water systems in Imperial County?
By EPA's size categories, U.S. Gypsum Co is a very small system (500 people or fewer). Imperial County has 76 active public water systems. Its population served is well below the county average of 2,444 people per system, and accounts for 0.2% of the 185,748 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 U.S. Gypsum Co is about 35% below 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 U.S. Gypsum Co?
EPA lists U.S. Gypsum Co 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. 46 of the 76 active systems in Imperial County (61%) are also privately owned.
Does U.S. Gypsum Co have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2024. The violations listed here began between September 1983 and October 2024. By type: 9 monitoring and reporting, 1 required treatment not met, 1 reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 9 as resolved, 2 as unaddressed and 1 as archived. 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. 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 |
|---|---|---|---|---|
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Unaddressed |
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2022-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2011-01-31 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2010-08-31 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2000-11-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1998-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1998-02-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1993-07-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1983-09-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | 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.
U.S. Gypsum Co: frequently asked questions
Who runs U.S. Gypsum Co?
U.S. Gypsum Co (PWSID CA1300517) is a non-transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does U.S. Gypsum Co serve?
U.S. Gypsum Co reports serving 280 people through 1 service connection in Imperial County, California.
Where does U.S. Gypsum Co 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 U.S. Gypsum Co have any drinking water violations?
Of the 12 most recent violations in EPA's records, one 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 U.S. Gypsum Co'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, one is health-based, and the most recent began in October 2024. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find U.S. Gypsum Co's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. U.S. Gypsum Co 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 Imperial County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| El Centro, City of | Imperial | 43,772 | Community | Purchased surface water |
| Calexico, City of | Imperial | 40,357 | Community | Purchased surface water |
| Brawley, City of | Imperial | 26,862 | Community | Purchased surface water |
| Imperial, City of | Imperial | 21,591 | Community | Purchased surface water |
| Imperial Valley College | Imperial | 8,150 | Non-transient non-community | Surface water |
| Gswc - Calipatria | Imperial | 7,363 | 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, “U.S. Gypsum Co, PWSID CA1300517, California”, https://aquacensus.com/water-systems/california/u-s-gypsum-co-ca1300517 (data as of October 1, 2026).