Public water system · CA1000054
ActiveLas Deltas Mutual Water Company
At a glance
Las Deltas Mutual Water Company (PWSID CA1000054) is an active community water system in Fresno County, California. It reports serving 375 people through 75 service connections. Its primary water source is purchased groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in November 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
375
Service connections
75
Primary source
GWP
Purchased groundwater
System type
CWS
Community water system
System record
How does Las Deltas Mutual Water Company compare with other water systems in Fresno County?
By EPA's size categories, Las Deltas Mutual Water Company is a very small system (500 people or fewer). Fresno County has 328 active public water systems. Its population served is well below the county average of 3,205 people per system, and accounts for less than 0.1% of the 1,051,276 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 Las Deltas 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 Las Deltas Mutual Water Company?
EPA lists Las Deltas 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. 220 of the 328 active systems in Fresno County (67%) are also privately owned.
Does Las Deltas Mutual Water Company have drinking water violations?
Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in November 2024. The violations listed here began between April 2017 and November 2024. By type: 10 contaminant level above the legal limit, 1 monitoring and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total trihalomethanes (TTHM) (10 of them). EPA lists 10 as archived, 1 as resolved and 1 as addressed. 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. 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. Addressed means the violation is not resolved or archived and is covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2024-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2021-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Addressed |
| 2020-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2019-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2019-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2019-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2018-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2018-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2018-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2018-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2017-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2017-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | 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.
Las Deltas Mutual Water Company: frequently asked questions
Who runs Las Deltas Mutual Water Company?
Las Deltas Mutual Water Company (PWSID CA1000054) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Las Deltas Mutual Water Company serve?
Las Deltas Mutual Water Company reports serving 375 people through 75 service connections in Fresno County, California.
Where does Las Deltas 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 Las Deltas Mutual Water Company have any drinking water violations?
Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in November 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 Las Deltas 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. Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in November 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 Las Deltas Mutual Water Company's water quality report?
As a community water system, Las Deltas 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 Fresno County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Fresno | Fresno | 545,716 | Community | Surface water |
| City of Clovis | Fresno | 130,130 | Community | Surface water |
| California State University Fresno | Fresno | 41,000 | Community | Groundwater |
| Cws - Selma | Fresno | 26,517 | Community | Groundwater |
| City of Sanger | Fresno | 26,357 | Community | Groundwater |
| Reedley, City of | Fresno | 26,076 | 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, “Las Deltas Mutual Water Company, PWSID CA1000054, California”, https://aquacensus.com/water-systems/california/las-deltas-mutual-water-company-ca1000054 (data as of October 1, 2026).