Public water system · IL1450100
ActiveDuquoin
At a glance
Duquoin (PWSID IL1450100) is an active community water system in Perry County, Illinois. It reports serving 7,169 people through 3,039 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
7,169
Service connections
3,039
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Duquoin compare with other water systems in Perry County?
By EPA's size categories, Duquoin is a medium system (3,301 to 10,000 people). Perry County has 9 active public water systems, and Duquoin is the largest of them by population served. Its population served is about 3.4 times the county average of 2,113 people per system, and accounts for 38% of the 19,020 people reported by systems filed under the county. Across Illinois, the 3,872 active systems average 3,204 people each. Nationally, the average active community water system reports serving 6,703 people, so Duquoin is roughly in line with 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. Illinois has 1,773 active community water systems, 46% of the state's 3,872 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 619 Illinois systems (16%) list purchased surface water as their primary source.
Who owns and regulates Duquoin?
EPA lists Duquoin as owned by a local government. The IL state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 5 of the 9 active systems in Perry County (56%) are also owned by a local government.
Does Duquoin have drinking water violations?
Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in January 2026. The violations listed here began between February 1998 and January 2026. By type: 5 monitoring and reporting, 2 public notice, recordkeeping or other, 2 contaminant level above the legal limit, 1 reporting, 1 monitoring and 1 required treatment not met. The contaminant or rule involved most often is Lead and Copper Rule (2 of them). EPA lists 8 as resolved, 2 as unaddressed and 2 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement. 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 reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2025-08-22 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2025-07-02 | ReportingNotification, Known or Potential LSL · code 4H | Lead and Copper Rule Revisionscode 5200 | No | Resolved |
| 2025-07-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2025-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloraminecode 1006 | No | Resolved |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Unaddressed |
| 2023-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2023-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2020-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2015-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 1998-02-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1998-02-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | 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.
Duquoin: frequently asked questions
Who runs Duquoin?
Duquoin (PWSID IL1450100) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Duquoin serve?
Duquoin reports serving 7,169 people through 3,039 service connections in Perry County, Illinois.
Where does Duquoin get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Duquoin have any drinking water violations?
Of the 12 most recent violations in EPA's records, 3 are 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 Duquoin'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, 3 are 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 IL state drinking water program.
Where can I find Duquoin's water quality report?
As a community water system, Duquoin 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 Perry County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Pinckneyville | Perry | 5,804 | Community | Surface water |
| Pinckneyville Correctional Center | Perry | 2,470 | Community | Purchased groundwater |
| Tamaroa | Perry | 2,197 | Community | Purchased surface water |
| Willisville | Perry | 799 | Community | Purchased surface water |
| Cutler | Perry | 463 | Community | Groundwater |
| Crossroads MHP | Perry | 53 | Community | Purchased surface water |
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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, “Duquoin, PWSID IL1450100, Illinois”, https://aquacensus.com/water-systems/illinois/duquoin-il1450100 (data as of October 1, 2026).