Public water system · IL0310200
ActiveSouth Barrington
At a glance
South Barrington (PWSID IL0310200) is an active community water system in Cook County, Illinois. It reports serving 1,175 people through 439 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list one violation for this system; it is not health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,175
Service connections
439
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does South Barrington compare with other water systems in Cook County?
By EPA's size categories, South Barrington is a small system (501 to 3,300 people). Cook County has 251 active public water systems. Its population served is well below the county average of 20,993 people per system, and accounts for less than 0.1% of the 5,269,212 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 South Barrington is well below 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. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,808 Illinois systems (73%) list groundwater as their primary source.
Who owns and regulates South Barrington?
EPA lists South Barrington 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. 134 of the 251 active systems in Cook County (53%) are also owned by a local government.
Does South Barrington have drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in July 2025. By type: 1 public notice, recordkeeping or other. The contaminant or rule involved is Consumer Confidence Rule. EPA lists 1 as unaddressed. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Unaddressed |
The one violation in EPA's records.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.
South Barrington: frequently asked questions
Who runs South Barrington?
South Barrington (PWSID IL0310200) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does South Barrington serve?
South Barrington reports serving 1,175 people through 439 service connections in Cook County, Illinois.
Where does South Barrington get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does South Barrington have any drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in July 2025. 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 South Barrington'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. EPA's records list one violation for this system; it is not health-based, and the most recent began in July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find South Barrington's water quality report?
As a community water system, South Barrington 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 Cook County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Chicago | Cook | 2,721,308 | Community | Surface water |
| Cicero | Cook | 83,000 | Community | Purchased surface water |
| Schaumburg | Cook | 75,750 | Community | Purchased surface water |
| Evanston | Cook | 74,486 | Community | Surface water |
| Arlington Heights | Cook | 73,320 | Community | Purchased surface water |
| Palatine | Cook | 70,875 | 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, “South Barrington, PWSID IL0310200, Illinois”, https://aquacensus.com/water-systems/illinois/south-barrington-il0310200 (data as of October 1, 2026).