Public water system · IL1670300
ActiveChatham
At a glance
Chatham (PWSID IL1670300) is an active community water system in Sangamon County, Illinois. It reports serving 16,423 people through 6,569 service connections. Its primary water source is purchased groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2017.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
16,423
Service connections
6,569
Primary source
GWP
Purchased groundwater
System type
CWS
Community water system
System record
How does Chatham compare with other water systems in Sangamon County?
By EPA's size categories, Chatham is a large system (10,001 to 100,000 people). Sangamon County has 43 active public water systems, and Chatham is the 2nd-largest of them by population served. Its population served is about 3.9 times the county average of 4,245 people per system, and accounts for 9% of the 182,536 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 Chatham is about 145% 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 groundwater means the system buys groundwater from another public water system rather than drawing its own. 348 Illinois systems (9%) list purchased groundwater as their primary source.
Who owns and regulates Chatham?
EPA lists Chatham 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 43 active systems in Sangamon County (47%) are also owned by a local government.
Does Chatham have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2017. The violations listed here began between July 2003 and January 2017. By type: 7 public notice, recordkeeping or other, 4 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Consumer Confidence Rule (6 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 |
|---|---|---|---|---|
| 2017-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2017-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2016-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2012-09-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2012-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | 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 |
| 2008-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2006-11-30 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2006-08-25 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2005-10-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2003-07-01 | 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.
Chatham: frequently asked questions
Who runs Chatham?
Chatham (PWSID IL1670300) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Chatham serve?
Chatham reports serving 16,423 people through 6,569 service connections in Sangamon County, Illinois.
Where does Chatham get its water?
EPA SDWIS lists this system's primary water source as purchased groundwater. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own.
Does Chatham 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 January 2017. 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 Chatham'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 January 2017. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Chatham's water quality report?
As a community water system, Chatham 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 Sangamon County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Springfield | Sangamon | 117,444 | Community | Surface water |
| Curran-Gardner Township PWD | Sangamon | 6,651 | Community | Groundwater |
| Williamsville | Sangamon | 6,198 | Community | Purchased surface water |
| Auburn | Sangamon | 4,574 | Community | Purchased surface water |
| Riverton | Sangamon | 4,279 | Community | Groundwater |
| Rochester | Sangamon | 3,856 | 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, “Chatham, PWSID IL1670300, Illinois”, https://aquacensus.com/water-systems/illinois/chatham-il1670300 (data as of October 1, 2026).