IL
IL drinking water
1,784 active community water systems serve 12,118,976 people in IL. Browse the largest utilities, see how groundwater and surface water sources are split, and dig into individual system pages for violations and lead service line status.
At a glance
- Community systems
- 1,784
- People served
- 12.1M
- Groundwater systems
- 66%
- 1,169 systems
- Surface water systems
- 34%
- 615 systems
Largest community water systems by population served
- 1. CHICAGO
CHICAGO · PWSID IL0316000
2.7M served - 2. AURORA
AURORA · PWSID IL0894070
183k served - 3. JOLIET
JOLIET · PWSID IL1970450
160k served - 4. NAPERVILLE
NAPERVILLE · PWSID IL0434670
156k served - 5. IL AMERICAN-CHAMPAIGN
GODFREY · PWSID IL0195300
150k served - 6. ROCKFORD
ROCKFORD · PWSID IL2010300
147k served - 7. IL AMERICAN-PEORIA
GODFREY · PWSID IL1435030
138k served - 8. IL AMERICAN-EAST ST LOUIS
GODFREY · PWSID IL1635040
131k served - 9. SPRINGFIELD
SPRINGFIELD · PWSID IL1671200
117k served - 10. ELGIN
ELGIN · PWSID IL0894380
115k served
Cities with the most served population
Communities with the largest aggregate population across all community water systems based in that city. Click through for the per-city utility list.
- Chicago · 2.8M
- Godfrey · 767k
- Kankakee · 189k
- Aurora · 184k
- Joliet · 166k
- Naperville · 156k
- Rockford · 148k
- Springfield · 130k
- Elgin · 117k
- Waukegan · 87k
- Decatur · 85k
- Libertyville · 85k
- Cicero · 83k
- Bloomington · 82k
- Schaumburg · 76k
- Evanston · 74k
- Skokie · 74k
- Arlington Heights · 73k
- Palatine · 71k
- Des Plaines · 61k
- Normal · 60k
- Oak Lawn · 58k
- Orland Park · 58k
- Berwyn · 57k
- Tinley Park · 57k
- Oak Park · 55k
- Wheaton · 54k
- Dekalb · 52k
- Moline · 51k
- Romeoville · 50k
- Plainfield · 50k
- Hoffman Estates · 50k
- Downers Grove · 49k
- Quincy · 48k
- Glenview · 48k
- Rock Island · 47k
- O'Fallon · 47k
- Northbrook · 46k
- Elmhurst · 45k
- Lombard · 45k
- Buffalo Grove · 43k
- St. Charles · 43k
- Dieterich · 43k
- Mchenry · 42k
- Bartlett · 42k
- Mount Prospect · 41k
- Crystal Lake · 41k
- Carol Stream · 40k
- Park Ridge · 40k
- Wheeling · 40k
- East Peoria · 40k
- Streamwood · 40k
- Oswego · 38k
- Addison · 38k
- Carpentersville · 38k
- Hanover Park · 37k
- Calumet City · 37k
- Edwardsville · 37k
- Marion · 36k
- Machesney Park · 36k
Showing the 60 largest cities by served population. 983 smaller communities also have pages on MyTapWater.us; reach them through the sitemap or via the address lookup.
Community water fluoridation in IL
State- and county-level aggregates from CDC's Water Fluoridation Reporting System. Per-utility fluoridation status is not in the bulk dataset; for a specific system, see the link below.
- Population on fluoridated water (2020)
- 98.4%
- 11,457,094 of 11,640,823 on CWS
- Community systems fluoridating
- 1,639 of 1,815
- 859 actively adjust fluoride
- Counties with 2020 data
- 102
- State shares per-system data on MWF
Trend over time
- 202098.4%
- 201898.2%
- 201698.5%
Highest fluoridation rate by county
- Kane100.0%
- St. Clair100.0%
- Sangamon100.0%
- Macon100.0%
- Marion100.0%
- Williamson100.0%
- Kendall100.0%
- Jackson100.0%
- Macoupin100.0%
- Knox100.0%
Lowest fluoridation rate by county
- Grundy69.4%
- Edwards84.4%
- Will87.6%
- Rock Island88.4%
- Wayne90.4%
- Henderson90.8%
- La Salle92.4%
- Carroll95.0%
- Ogle95.1%
- McDonough96.4%
Find your specific utility's status
IL shares per-system fluoridation data on CDC's My Water's Fluoride site. Search by water system to see whether a specific utility adjusts fluoride.