Public water system · IL1635000
ActiveCahokia Heights
At a glance
Cahokia Heights (PWSID IL1635000) is an active community water system in St. Clair County, Illinois. It reports serving 12,528 people through 5,011 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's Safe Drinking Water Act records list no violations for this system.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
12,528
Service connections
5,011
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Cahokia Heights compare with other water systems in St. Clair County?
By EPA's size categories, Cahokia Heights is a large system (10,001 to 100,000 people). St. Clair County has 42 active public water systems, and Cahokia Heights is the 4th-largest of them by population served. Its population served is about twice the county average of 6,082 people per system, and accounts for 4.9% of the 255,459 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 Cahokia Heights is about 87% 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 Cahokia Heights?
EPA lists Cahokia Heights 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. 22 of the 42 active systems in St. Clair County (52%) are also owned by a local government.
Does Cahokia Heights have drinking water violations?
No SDWA violations on record.
EPA's SDWA violation and enforcement data (via EPA ECHO, updated quarterly) lists no violations for Cahokia Heights. For the latest compliance status, check EPA ECHO for current compliance history.
Cahokia Heights: frequently asked questions
Who runs Cahokia Heights?
Cahokia Heights (PWSID IL1635000) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Cahokia Heights serve?
Cahokia Heights reports serving 12,528 people through 5,011 service connections in St. Clair County, Illinois.
Where does Cahokia Heights 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 Cahokia Heights have any drinking water violations?
EPA's Safe Drinking Water Act records list no violations for this system.
Is Cahokia Heights' 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. EPA's Safe Drinking Water Act records list no violations for this system. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Cahokia Heights' water quality report?
As a community water system, Cahokia Heights 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 St. Clair County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Il American-East St Louis | St. Clair | 131,368 | Community | Surface water |
| O Fallon | St. Clair | 46,603 | Community | Purchased surface water |
| Caseyville | St. Clair | 13,798 | Community | Purchased surface water |
| Mascoutah | St. Clair | 8,759 | Community | Purchased surface water |
| American Water Oper and Maintenance, LLC | St. Clair | 6,779 | Community | Purchased surface water |
| Lebanon | St. Clair | 4,714 | 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, “Cahokia Heights, PWSID IL1635000, Illinois”, https://aquacensus.com/water-systems/illinois/cahokia-heights-il1635000 (data as of October 1, 2026).