Public water system · AZ0408040
ActiveEpcor - Willow Valley/King Street
At a glance
Epcor - Willow Valley/King Street (PWSID AZ0408040) is an active community water system in Mohave County, Arizona. It reports serving 3,408 people through 1,421 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, 2 are health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
3,408
Service connections
1,421
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Epcor - Willow Valley/King Street compare with other water systems in Mohave County?
By EPA's size categories, Epcor - Willow Valley/King Street is a medium system (3,301 to 10,000 people). Mohave County has 119 active public water systems. Its population served is about 75% above the county average of 1,948 people per system, and accounts for 1.5% of the 231,847 people reported by systems filed under the county. Across Arizona, the 1,769 active systems average 4,369 people each. Nationally, the average active community water system reports serving 6,703 people, so Epcor - Willow Valley/King Street is about half of 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. Arizona has 936 active community water systems, 53% of the state's 1,769 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,612 Arizona systems (91%) list groundwater as their primary source.
Who owns and regulates Epcor - Willow Valley/King Street?
EPA lists Epcor - Willow Valley/King Street as privately owned. The AZ state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 70 of the 119 active systems in Mohave County (59%) are also privately owned.
Does Epcor - Willow Valley/King Street have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2025. The violations listed here began between January 2012 and July 2025. By type: 8 monitoring and reporting, 2 contaminant level above the legal limit, 1 reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Chlorite (3 of them). EPA lists 11 as resolved and 1 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 |
|---|---|---|---|---|
| 2025-07-02 | ReportingNotification, Known or Potential LSL · code 4H | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2025-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Chloritecode 1009 | Yes | Resolved |
| 2022-12-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloritecode 1009 | No | Resolved |
| 2022-06-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloritecode 1009 | No | Resolved |
| 2021-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2021-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2021-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2015-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2015-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2013-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2013-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2012-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | 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.
Epcor - Willow Valley/King Street: frequently asked questions
Who runs Epcor - Willow Valley/King Street?
Epcor - Willow Valley/King Street (PWSID AZ0408040) is a community water system privately owned. It is regulated by the AZ state drinking water program.
How many people does Epcor - Willow Valley/King Street serve?
Epcor - Willow Valley/King Street reports serving 3,408 people through 1,421 service connections in Mohave County, Arizona.
Where does Epcor - Willow Valley/King Street 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 Epcor - Willow Valley/King Street have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2025. 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 Epcor - Willow Valley/King Street'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, 2 are health-based, and the most recent began in July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the AZ state drinking water program.
Where can I find Epcor - Willow Valley/King Street's water quality report?
As a community water system, Epcor - Willow Valley/King Street 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 Mohave County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Lake Havasu City of | Mohave | 54,610 | Community | Groundwater |
| Kingman Municipal Water | Mohave | 45,000 | Community | Groundwater |
| Bullhead City Mohave | Mohave | 36,330 | Community | Groundwater |
| Bermuda Water Company Inc. | Mohave | 25,000 | Community | Groundwater |
| Valley Pioneers Water Company Inc. | Mohave | 6,063 | Community | Groundwater |
| North Mohave Valley | Mohave | 5,190 | 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, “Epcor - Willow Valley/King Street, PWSID AZ0408040, Arizona”, https://aquacensus.com/water-systems/arizona/epcor-willow-valley-king-street-az0408040 (data as of October 1, 2026).