Public water system · IL1990550
ActiveMarion
At a glance
Marion (PWSID IL1990550) is an active community water system in Williamson County, Illinois. It reports serving 16,855 people through 9,812 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, 2 are health-based, and the most recent began in August 2013.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
16,855
Service connections
9,812
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Marion compare with other water systems in Williamson County?
By EPA's size categories, Marion is a large system (10,001 to 100,000 people). Williamson County has 25 active public water systems, and Marion is the largest of them by population served. Its population served is about 5.6 times the county average of 3,018 people per system, and accounts for 22% of the 75,458 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 Marion is about 151% above 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 Marion?
EPA lists Marion 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. 20 of the 25 active systems in Williamson County (80%) are also owned by a local government.
Does Marion have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in August 2013. The violations listed here began between April 1988 and August 2013. By type: 9 monitoring and reporting, 1 public notice, recordkeeping or other, 1 required treatment not met and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Carbon, total (3 of them). EPA lists 6 as resolved and 6 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 |
|---|---|---|---|---|
| 2013-08-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2013-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloraminecode 1006 | No | Resolved |
| 2011-08-01 | Monitoring and reportingMonitoring, Turbidity (Enhanced SWTR) · code 38 | Interim Enhanced Surface Water Treatment Rulecode 0300 | No | Archived |
| 2011-08-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Archived |
| 2011-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2011-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Archived |
| 2003-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Resolved |
| 2003-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Resolved |
| 2002-06-01 | Required treatment not metMonthly Turbidity Exceed (Enhanced SWTR) · code 44 | Interim Enhanced Surface Water Treatment Rulecode 0300 | Yes | Resolved |
| 1997-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1988-04-01 | Monitoring and reportingMonitoring, Check/Repeat/Confirmation · code 04 | Chromiumcode 1020 | No | Archived |
| 1988-04-01 | Monitoring and reportingMonitoring, Check/Repeat/Confirmation · code 04 | Cadmiumcode 1015 | No | 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.
Marion: frequently asked questions
Who runs Marion?
Marion (PWSID IL1990550) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Marion serve?
Marion reports serving 16,855 people through 9,812 service connections in Williamson County, Illinois.
Where does Marion 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 Marion 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 August 2013. 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 Marion'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 August 2013. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Marion's water quality report?
As a community water system, Marion 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 Williamson County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Herrin | Williamson | 12,747 | Community | Purchased surface water |
| Lake of Egypt PWD | Williamson | 11,368 | Community | Surface water |
| Carterville | Williamson | 6,528 | Community | Purchased surface water |
| Coal Valley PWD | Williamson | 4,023 | Community | Purchased surface water |
| Corinth PWD | Williamson | 3,927 | Community | Purchased surface water |
| Johnston City | Williamson | 3,509 | Community | Purchased surface water |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Marion, PWSID IL1990550, Illinois”, https://aquacensus.com/water-systems/illinois/marion-il1990550 (data as of October 1, 2026).