Public water system · IL1570100
ActiveChester
At a glance
Chester (PWSID IL1570100) is an active community water system in Randolph County, Illinois. It reports serving 8,407 people through 2,826 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
8,407
Service connections
2,826
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Chester compare with other water systems in Randolph County?
By EPA's size categories, Chester is a medium system (3,301 to 10,000 people). Randolph County has 21 active public water systems, and Chester is the largest of them by population served. Its population served is about 5.9 times the county average of 1,413 people per system, and accounts for 28% of the 29,678 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 Chester is about 25% 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. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 89 Illinois systems (2.3%) list surface water as their primary source.
Who owns and regulates Chester?
EPA lists Chester 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. 12 of the 21 active systems in Randolph County (57%) are also owned by a local government.
Does Chester have drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in January 2026. The violations listed here began between November 2003 and January 2026. By type: 5 monitoring and reporting, 4 required treatment not met and 3 public notice, recordkeeping or other. The contaminant or rule involved most often is Public Notice (3 of them). EPA lists 10 as resolved 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. 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 | Simazinecode 2037 | No | Archived |
| 2026-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Atrazinecode 2050 | No | Archived |
| 2013-03-16 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2013-01-01 | Required treatment not metMonthly Turbidity Exceed (Enhanced SWTR) · code 44 | Interim Enhanced Surface Water Treatment Rulecode 0300 | Yes | Resolved |
| 2012-02-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2012-01-01 | Required treatment not metTreatment Technique Precursor Removal · code 46 | Carbon, totalcode 2920 | Yes | Resolved |
| 2012-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2011-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2008-03-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2008-02-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 2003-11-09 | Public notice, recordkeeping or otherPublic Notification Violation without NPDWR Violation · code 76 | Public Noticecode 7500 | No | Resolved |
| 2003-11-09 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | 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.
Chester: frequently asked questions
Who runs Chester?
Chester (PWSID IL1570100) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Chester serve?
Chester reports serving 8,407 people through 2,826 service connections in Randolph County, Illinois.
Where does Chester get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Chester have any drinking water violations?
Of the 12 most recent violations in EPA's records, 4 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 Chester'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, 4 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 Chester's water quality report?
As a community water system, Chester 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 Randolph County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Sparta | Randolph | 4,395 | Community | Surface water |
| Red Bud | Randolph | 3,804 | Community | Groundwater |
| Menard Correctional Center | Randolph | 2,950 | Community | Purchased surface water |
| Egyptian Water Company | Randolph | 2,330 | Community | Purchased surface water |
| Steeleville | Randolph | 1,960 | Community | Groundwater |
| Coulterville | Randolph | 1,052 | 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, “Chester, PWSID IL1570100, Illinois”, https://aquacensus.com/water-systems/illinois/chester-il1570100 (data as of October 1, 2026).