Public water system · AZ0408129
ActiveEpcor - Willow Valley/Lake Cimarron
At a glance
Epcor - Willow Valley/Lake Cimarron (PWSID AZ0408129) is an active community water system in Mohave County, Arizona. It reports serving 596 people through 248 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 March 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
596
Service connections
248
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Epcor - Willow Valley/Lake Cimarron compare with other water systems in Mohave County?
By EPA's size categories, Epcor - Willow Valley/Lake Cimarron is a small system (501 to 3,300 people). Mohave County has 119 active public water systems. Its population served is well below the county average of 1,948 people per system, and accounts for 0.3% 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/Lake Cimarron 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. 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/Lake Cimarron?
EPA lists Epcor - Willow Valley/Lake Cimarron 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/Lake Cimarron have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in March 2023. The violations listed here began between July 2010 and March 2023. By type: 8 monitoring and reporting, 3 public notice, recordkeeping or other and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Chlorite (3 of them). EPA lists 12 as resolved. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2023-03-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloritecode 1009 | No | Resolved |
| 2022-12-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloritecode 1009 | No | Resolved |
| 2022-02-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2020-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloritecode 1009 | No | Resolved |
| 2020-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorine dioxidecode 1008 | No | Resolved |
| 2017-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | 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 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2013-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2011-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2010-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | 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.
Epcor - Willow Valley/Lake Cimarron: frequently asked questions
Who runs Epcor - Willow Valley/Lake Cimarron?
Epcor - Willow Valley/Lake Cimarron (PWSID AZ0408129) is a community water system privately owned. It is regulated by the AZ state drinking water program.
How many people does Epcor - Willow Valley/Lake Cimarron serve?
Epcor - Willow Valley/Lake Cimarron reports serving 596 people through 248 service connections in Mohave County, Arizona.
Where does Epcor - Willow Valley/Lake Cimarron 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/Lake Cimarron 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 March 2023. 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/Lake Cimarron'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 March 2023. 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/Lake Cimarron's water quality report?
As a community water system, Epcor - Willow Valley/Lake Cimarron 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/Lake Cimarron, PWSID AZ0408129, Arizona”, https://aquacensus.com/water-systems/arizona/epcor-willow-valley-lake-cimarron-az0408129 (data as of October 1, 2026).