Public water system · CA5400718
ActiveWilliams Mutual Water Company
At a glance
Williams Mutual Water Company (PWSID CA5400718) is an active community water system in Tulare County, California. It reports serving 165 people through 50 service connections. 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
165
Service connections
50
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Williams Mutual Water Company compare with other water systems in Tulare County?
By EPA's size categories, Williams Mutual Water Company is a very small system (500 people or fewer). Tulare County has 274 active public water systems. Its population served is well below the county average of 1,700 people per system, and accounts for less than 0.1% of the 465,710 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 Williams 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. 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 Williams Mutual Water Company?
EPA lists Williams 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. 184 of the 274 active systems in Tulare County (67%) are also privately owned.
Does Williams Mutual Water Company 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 January 2007 and October 2024. By type: 7 monitoring and reporting, 2 public notice, recordkeeping or other, 1 required treatment not met, 1 reporting and 1 monitoring. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 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.
| 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 |
| 2018-05-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2015-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2011-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2011-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-04-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2008-05-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
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.
Williams Mutual Water Company: frequently asked questions
Who runs Williams Mutual Water Company?
Williams Mutual Water Company (PWSID CA5400718) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Williams Mutual Water Company serve?
Williams Mutual Water Company reports serving 165 people through 50 service connections in Tulare County, California.
Where does Williams Mutual Water Company 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 Williams Mutual Water Company 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 Williams 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, one is 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 Williams Mutual Water Company's water quality report?
As a community water system, Williams 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 Tulare County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Cws - Visalia | Tulare | 148,496 | Community | Groundwater |
| Tulare, City of | Tulare | 72,241 | Community | Groundwater |
| Porterville, City of | Tulare | 63,487 | Community | Groundwater |
| Dinuba, City of | Tulare | 27,281 | Community | Groundwater |
| Lindsay, City of | Tulare | 12,659 | Community | Surface water |
| Exeter, City of | Tulare | 11,169 | 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, “Williams Mutual Water Company, PWSID CA5400718, California”, https://aquacensus.com/water-systems/california/williams-mutual-water-company-ca5400718 (data as of October 1, 2026).