Public water system · AZ0406001
ActiveDuncan Town of
At a glance
Town of Duncan (PWSID AZ0406001) is an active community water system in Greenlee County, Arizona. It reports serving 605 people through 300 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
605
Service connections
300
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Town of Duncan compare with other water systems in Greenlee County?
By EPA's size categories, Town of Duncan is a small system (501 to 3,300 people). Greenlee County has 11 active public water systems, and Town of Duncan is the 3rd-largest of them by population served. Its population served is about 19% below the county average of 743 people per system, and accounts for 7.4% of the 8,173 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 Town of Duncan 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 Town of Duncan?
EPA lists Town of Duncan as owned by a local government. 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. 3 of the 11 active systems in Greenlee County (27%) are also owned by a local government.
Does Town of Duncan have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2026. The violations listed here began between April 2025 and January 2026. By type: 10 monitoring and reporting and 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Di(2-ethylhexyl) phthalate (2 of them). EPA lists 11 as resolved 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. 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 |
|---|---|---|---|---|
| 2026-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Archived |
| 2025-10-02 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2025-07-02 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2025-07-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Resolved |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlorobenzenecode 2989 | No | Resolved |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Ethylbenzenecode 2992 | No | Resolved |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,2-Trichloroethanecode 2985 | No | Resolved |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | p-Dichlorobenzenecode 2969 | No | Resolved |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Tetrachloroethylenecode 2987 | No | Resolved |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Styrenecode 2996 | No | Resolved |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Xylenes, Totalcode 2955 | No | Resolved |
| 2025-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,1-Trichloroethanecode 2981 | 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.
Town of Duncan: frequently asked questions
Who runs Town of Duncan?
Town of Duncan (PWSID AZ0406001) is a community water system owned by a local government. It is regulated by the AZ state drinking water program.
How many people does Town of Duncan serve?
Town of Duncan reports serving 605 people through 300 service connections in Greenlee County, Arizona.
Where does Town of Duncan 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 Town of Duncan have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in January 2026. 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 Town of Duncan'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, none is health-based, and the most recent began in January 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the AZ state drinking water program.
Where can I find Town of Duncan's water quality report?
As a community water system, Town of Duncan 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 Greenlee County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Morenci Water Elec Co Main | Greenlee | 4,108 | Community | Surface water |
| Morenci Water Elec Co Clifton | Greenlee | 1,678 | Community | Groundwater |
| Cs Verde Lee Water Company | Greenlee | 604 | Community | Groundwater |
| Duncan Elementary School | Greenlee | 450 | Non-transient non-community | Purchased groundwater |
| Cs Loma Linda Water Company | Greenlee | 351 | Community | Groundwater |
| Valley View Mhc & Rv Park | Greenlee | 142 | 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, “Duncan Town of, PWSID AZ0406001, Arizona”, https://aquacensus.com/water-systems/arizona/duncan-town-of-az0406001 (data as of October 1, 2026).