Illinois water providers
Find published drinking-water records, providers, and official agency resources for Illinois. Review sources, sample dates, and coverage.
Official drinking-water resources
The responsible agency may differ for tribal systems. Record availability and sample dates vary by provider.
Community systems appear first. Sort: Population served · A–Z
Public water systems
5,095 systems in the imported directory. Includes community systems, schools, workplaces, and other public systems.
- ChicagoIL0316000 · CWS · Population served: 2,721,308
- AuroraIL0894070 · CWS · Population served: 183,000
- JolietIL1970450 · CWS · Population served: 160,000
- NapervilleIL0434670 · CWS · Population served: 156,406
- Il American-ChampaignIL0195300 · CWS · Population served: 150,000
- RockfordIL2010300 · CWS · Population served: 147,051
- Il American-PeoriaIL1435030 · CWS · Population served: 137,575
- Il American-East St LouisIL1635040 · CWS · Population served: 131,368
- SpringfieldIL1671200 · CWS · Population served: 117,444
- ElginIL0894380 · CWS · Population served: 114,797
- WaukeganIL0971900 · CWS · Population served: 87,149
- CiceroIL0310510 · CWS · Population served: 83,000
- Aqua Illinois-KankakeeIL0915030 · CWS · Population served: 80,000
- BloomingtonIL1130200 · CWS · Population served: 77,610
- DecaturIL1150150 · CWS · Population served: 76,122
- SchaumburgIL0314890 · CWS · Population served: 75,750
- EvanstonIL0310810 · CWS · Population served: 74,486
- Il American-West SuburbanIL1974151 · CWS · Population served: 73,978
- Arlington HeightsIL0314030 · CWS · Population served: 73,320
- PalatineIL0312340 · CWS · Population served: 70,875
- SkokieIL0312880 · CWS · Population served: 66,422
- Des PlainesIL0310630 · CWS · Population served: 60,675
- Oak LawnIL0312220 · CWS · Population served: 58,362
- Orland ParkIL0312310 · CWS · Population served: 58,020
- BerwynIL0310210 · CWS · Population served: 57,250
- Tinley ParkIL0314910 · CWS · Population served: 56,703
- Oak ParkIL0312250 · CWS · Population served: 54,583
- WheatonIL0431050 · CWS · Population served: 53,970
- NormalIL1130900 · CWS · Population served: 52,736
- RomeovilleIL1970900 · CWS · Population served: 50,458
- Hoffman EstatesIL0311290 · CWS · Population served: 50,179
- PlainfieldIL1970800 · CWS · Population served: 50,000
- Downers GroveIL0430300 · CWS · Population served: 49,425
- GlenviewIL0311020 · CWS · Population served: 47,856
- O FallonIL1631100 · CWS · Population served: 46,603
- Il American-AltonIL1195150 · CWS · Population served: 46,127
- ElmhurstIL0430350 · CWS · Population served: 45,000
- MolineIL1610450 · CWS · Population served: 44,500
- LombardIL0430600 · CWS · Population served: 44,476
- Buffalo GroveIL0314180 · CWS · Population served: 43,212
- QuincyIL0010650 · CWS · Population served: 42,000
- BartlettIL0314120 · CWS · Population served: 41,500
- Mount ProspectIL0311980 · CWS · Population served: 41,000
- Crystal LakeIL1110150 · CWS · Population served: 40,661
- DekalbIL0370100 · CWS · Population served: 40,290
- Carol StreamIL0430200 · CWS · Population served: 39,854
- Park RidgeIL0312460 · CWS · Population served: 39,800
- WheelingIL0314970 · CWS · Population served: 39,725
- StreamwoodIL0313060 · CWS · Population served: 39,577
- Rock IslandIL1610650 · CWS · Population served: 39,018
- OswegoIL0930150 · CWS · Population served: 38,169
- AddisonIL0430050 · CWS · Population served: 38,017
- CarpentersvilleIL0890200 · CWS · Population served: 37,983
- Hanover ParkIL0314480 · CWS · Population served: 37,470
- Calumet CityIL0310390 · CWS · Population served: 37,000
- North Park PwdIL2015500 · CWS · Population served: 35,580
- NorthbrookIL0312070 · CWS · Population served: 34,407
- Il American-Granite CityIL1195030 · CWS · Population served: 33,572
- WoodridgeIL0431250 · CWS · Population served: 33,566
- Vernon Hills - Lake Co PwIL0971750 · CWS · Population served: 33,207
- Glendale HeightsIL0430400 · CWS · Population served: 33,176
- St CharlesIL0894830 · CWS · Population served: 33,103
- Elk Grove VillageIL0314400 · CWS · Population served: 31,802
- Il American-PekinIL1795040 · CWS · Population served: 31,731
- GalesburgIL0950200 · CWS · Population served: 31,620
- MundeleinIL0971150 · CWS · Population served: 31,500
- AlgonquinIL1110050 · CWS · Population served: 30,700
- GurneeIL0970350 · CWS · Population served: 30,193
- Highland ParkIL0970500 · CWS · Population served: 30,176
- Aqua Illinois-Vermilion CountyIL1835120 · CWS · Population served: 30,106
- Aqua Illinois-North Maine UtilitiesIL0315350 · CWS · Population served: 30,043
- South Stickny SdIL0317370 · CWS · Population served: 30,000
- Ej Water CooperativeIL0790010 · CWS · Population served: 29,720
- CollinsvilleIL1194280 · CWS · Population served: 29,500
- NilesIL0312010 · CWS · Population served: 29,350
- LansingIL0311590 · CWS · Population served: 29,076
- MontgomeryIL0894690 · CWS · Population served: 28,956
- Glen EllynIL0430450 · CWS · Population served: 28,850
- Lake In The HillsIL1110400 · CWS · Population served: 28,661
- HuntleyIL1110350 · CWS · Population served: 28,495
- New LenoxIL1970700 · CWS · Population served: 27,690
- Oak ForestIL0312190 · CWS · Population served: 27,478
- Round Lake BeachIL0971550 · CWS · Population served: 27,200
- WilmetteIL0313300 · CWS · Population served: 27,087
- EdwardsvilleIL1190250 · CWS · Population served: 26,808
- Chicago HeightsIL0310450 · CWS · Population served: 26,184
- BataviaIL0894130 · CWS · Population served: 26,098
- WoodstockIL1110950 · CWS · Population served: 25,630
- BelvidereIL0070050 · CWS · Population served: 25,339
- Morton GroveIL0311950 · CWS · Population served: 25,297
- West ChicagoIL0430900 · CWS · Population served: 25,166
- Elmwood ParkIL0310780 · CWS · Population served: 25,000
- HarveyIL0311110 · CWS · Population served: 25,000
- Il American-Homer TownshipIL1970100 · CWS · Population served: 24,543
- ZionIL0972000 · CWS · Population served: 24,442
- LisleIL0430551 · CWS · Population served: 24,223
- Melrose ParkIL0311860 · CWS · Population served: 24,206
- WestmontIL0430950 · CWS · Population served: 24,161
- MaywoodIL0311830 · CWS · Population served: 24,090
- FrankfortIL1970400 · CWS · Population served: 24,000