Water Service Outages in Illinois by City
The most common health-based drinking water violation in Illinois since 2015 involves contaminant averages over the limit; 430 of 1,787 systems have had at least one violation.
Illinois drinking water record
Busiest year: 2024 (260 violations). Counted by the year the violation period began. Source: EPA SDWIS.
- Community water systems: 1,787 active systems serve about 12,093,685 people. 1,337 of them (75%) serve 3,300 people or fewer; 1,140 draw mainly on groundwater and 639 on surface water.
- Health-based violations since 2015: 1,131, at 430 systems (24% of all systems). That share is 18th of 50 states (1 = lowest).
- Most common problems: contaminant averages over the limit (659); lead and copper corrosion-control studies (65); disinfection byproduct precursors (58). Source: EPA SDWIS
- Largest system: Chicago, about 2,721,308 people, with 0 health-based violations since 2015. Source: EPA SDWIS
- Housing age: the median Illinois home was built in 1971 (US 1980). Older housing stock means more lead service lines left to replace. Source: US Census Bureau, ACS 2020–2024 (table B25035)
- Storm damage to water service: NOAA storm narratives mention water mains, boil water notices or lost water service in 4 episodes in Illinois since 2015. Source: NOAA Storm Events Database
- January 25, 2024, Will (flash flood): “Ice piled up against a guardrail and water reached the shoulder of Widows Road near the water treatment plant.” Source: NOAA Storm Events Database
- August 21, 2021, Marion (flash flood): “Town Creek rose above and out of its banks on the southeast side of town next to the water treatment plant.” Source: NOAA Storm Events Database
| System | People served | Main source | Health violations since 2015 |
|---|---|---|---|
| Chicago | 2,721,308 | Surface water | 0 |
| Aurora | 183,000 | Surface water | 0 |
| Joliet | 160,000 | Groundwater | 1 |
| Naperville | 156,406 | Bought surface water | 0 |
| Il American-Champaign | 150,000 | Groundwater | 0 |
| Rockford | 147,051 | Groundwater | 0 |
Source: EPA SDWIS.
Illinois is 2nd of 6 (1 = lowest share). Source: EPA SDWIS.
Checked September 2026.
Who to call in Illinois, city by city
10 Illinois cities on this site and the water utility for each. What to do while you wait is in our water service outage guide.
- Chicago Chicago Department of Water Management
- Aurora City of Aurora Water Production
- Joliet City of Joliet Public Utilities
- Naperville Naperville Department of Public Utilities – Water
- Rockford Rockford Water Division
- Elgin City of Elgin Water Department
- Springfield City Water, Light & Power (CWLP)
- Peoria Illinois American Water
- Waukegan City of Waukegan Water Utility
- Champaign Illinois American Water
Frequently asked questions
Is there a water service outage in Illinois right now?
Not on this site: no reports from Illinois in the last 24 hours.
How many public water systems are in Illinois?
EPA records list 1,787 active community water systems in Illinois, serving about 12,093,685 people. 75% serve 3,300 people or fewer.
How common are drinking water violations in Illinois?
Since 2015, 430 of 1,787 community water systems in Illinois (24%) have had at least one health-based violation, 1,131 in total.
What is the largest water system in Illinois?
Chicago, which EPA records list as serving about 2,721,308 people.
Report counts are user-submitted; other figures name their official source. How our data works
Cities in Illinois with Water Service Outages Information
Aurora
no reports in the last 24 hours · pop. 180,542
City of Aurora Water Production
Champaign
no reports in the last 24 hours · pop. 88,402
Illinois American Water
Chicago
no reports in the last 24 hours · pop. 2,693,976
Chicago Department of Water Management
Elgin
no reports in the last 24 hours · pop. 114,797
City of Elgin Water Department
Joliet
no reports in the last 24 hours · pop. 150,362
City of Joliet Public Utilities
Naperville
no reports in the last 24 hours · pop. 149,540
Naperville Department of Public Utilities – Water
Peoria
no reports in the last 24 hours · pop. 113,150
Illinois American Water
Rockford
no reports in the last 24 hours · pop. 148,655
Rockford Water Division
Springfield
no reports in the last 24 hours · pop. 114,230
City Water, Light & Power (CWLP)
Waukegan
no reports in the last 24 hours · pop. 89,078
City of Waukegan Water Utility