Illinois County Water Quality Reports

Adams County, IL: 5 Health Violations — 57/100 (2026)

2026 report: Adams County, IL scores 57/100 (Grade C). 19 ZIP codes analyzed. 27 EPA violations found. Free report with contaminant data and filter picks.

Alexander County, IL: 8 Violations — 73/100 (2026)

2026 report: Alexander County, IL scores 73/100 (Grade B). 8 ZIP codes analyzed. 8 EPA violations found. Free report with contaminant data and filter pi...

Bond County, IL: 4 Health Violations — 67/100 (2026)

2026 report: Bond County, IL scores 67/100 (Grade C). 6 ZIP codes analyzed. 32 EPA violations found. Free report with contaminant data and filter picks.

Boone County, IL: 12 Violations — 50/100 (2026)

2026 report: Boone County, IL scores 50/100 (Grade D). 8 ZIP codes analyzed. 12 EPA violations found. Free report with contaminant data and filter picks.

Brown County, IL: 1 Violation — 58/100 (2026)

2026 report: Brown County, IL scores 58/100 (Grade C). 1 ZIP code analyzed. 1 EPA violation found. Free report with contaminant data and filter picks.

Bureau County, IL: Lead Above EPA Limits — 59/100 (2026)

2026 report: Bureau County, IL scores 59/100 (Grade C). 24 ZIP codes analyzed. 56 EPA violations found. Lead above EPA limits. Free report with contamin...

Calhoun County, IL: 1 Health Violation — 46/100 (2026)

2026 report: Calhoun County, IL scores 46/100 (Grade D). 7 ZIP codes analyzed. 5 EPA violations found. Free report with contaminant data and filter picks.

Carroll County, IL: Lead Above EPA Limits — 58/100 (2026)

2026 report: Carroll County, IL scores 58/100 (Grade C). 7 ZIP codes analyzed. 14 EPA violations found. Lead above EPA limits. Free report with contamin...

Cass County, IL: 1 Health Violation — 53/100 (2026)

2026 report: Cass County, IL scores 53/100 (Grade D). 9 ZIP codes analyzed. 10 EPA violations found. Free report with contaminant data and filter picks.

Champaign County, IL: 2 Health Violations — 57/100 (2026)

2026 report: Champaign County, IL scores 57/100 (Grade C). 34 ZIP codes analyzed. 57 EPA violations found. Free report with contaminant data and filter ...

Christian County, IL: Lead Above EPA Limits — 68/100 (2026)

2026 report: Christian County, IL scores 68/100 (Grade C). 13 ZIP codes analyzed. 45 EPA violations found. Lead above EPA limits. Free report with conta...

Clark County, IL: 3 Health Violations — 69/100 (2026)

2026 report: Clark County, IL scores 69/100 (Grade C). 7 ZIP codes analyzed. 27 EPA violations found. Free report with contaminant data and filter picks.

Clay County, IL: 10 Violations — 70/100 (2026)

2026 report: Clay County, IL scores 70/100 (Grade B). 6 ZIP codes analyzed. 10 EPA violations found. Free report with contaminant data and filter picks.

Clinton County, IL: Lead Above EPA Limits — 67/100 (2026)

2026 report: Clinton County, IL scores 67/100 (Grade C). 15 ZIP codes analyzed. 74 EPA violations found. Lead above EPA limits. Free report with contami...

Coles County, IL: Lead Above EPA Limits — 54/100 (2026)

2026 report: Coles County, IL scores 54/100 (Grade D). 7 ZIP codes analyzed. 30 EPA violations found. Lead above EPA limits. Free report with contaminan...

Cook County, IL: Lead Above EPA Limits — 68/100 (2026)

2026 report: Cook County, IL scores 68/100 (Grade C). 219 ZIP codes analyzed. 1971 EPA violations found. Lead above EPA limits. Free report with contami...

Crawford County, IL: 1 Health Violation — 68/100 (2026)

2026 report: Crawford County, IL scores 68/100 (Grade C). 7 ZIP codes analyzed. 15 EPA violations found. Free report with contaminant data and filter pi...

Cumberland County, IL: 2 Health Violations — 68/100 (2026)

2026 report: Cumberland County, IL scores 68/100 (Grade C). 6 ZIP codes analyzed. 6 EPA violations found. Free report with contaminant data and filter p...

De Witt County, IL: Lead Above EPA Limits — 52/100 (2026)

2026 report: De Witt County, IL scores 52/100 (Grade D). 9 ZIP codes analyzed. 39 EPA violations found. Lead above EPA limits. Free report with contamin...

DeKalb County, IL: 4 Health Violations — 57/100 (2026)

2026 report: DeKalb County, IL scores 57/100 (Grade C). 12 ZIP codes analyzed. 120 EPA violations found. Free report with contaminant data and filter pi...

Douglas County, IL: 5 Health Violations — 55/100 (2026)

2026 report: Douglas County, IL scores 55/100 (Grade C). 7 ZIP codes analyzed. 20 EPA violations found. Free report with contaminant data and filter picks.

DuPage County, IL: Lead Above EPA Limits — 70/100 (2026)

2026 report: DuPage County, IL scores 70/100 (Grade B). 51 ZIP codes analyzed. 121 EPA violations found. Lead above EPA limits. Free report with contami...

Edgar County, IL: Lead Above EPA Limits — 52/100 (2026)

2026 report: Edgar County, IL scores 52/100 (Grade D). 8 ZIP codes analyzed. 48 EPA violations found. Lead above EPA limits. Free report with contaminan...

Edwards County, IL: 13 Violations — 63/100 (2026)

2026 report: Edwards County, IL scores 63/100 (Grade C). 7 ZIP codes analyzed. 13 EPA violations found. Free report with contaminant data and filter picks.

Effingham County, IL: 11 Health Violations — 70/100 (2026)

2026 report: Effingham County, IL scores 70/100 (Grade B). 7 ZIP codes analyzed. 55 EPA violations found. Free report with contaminant data and filter p...

Fayette County, IL: 7 Health Violations — 70/100 (2026)

2026 report: Fayette County, IL scores 70/100 (Grade B). 8 ZIP codes analyzed. 30 EPA violations found. Free report with contaminant data and filter picks.

Ford County, IL: Lead Above EPA Limits — 51/100 (2026)

2026 report: Ford County, IL scores 51/100 (Grade D). 9 ZIP codes analyzed. 21 EPA violations found. Lead above EPA limits. Free report with contaminant...

Franklin County, IL: Lead Above EPA Limits — 68/100 (2026)

2026 report: Franklin County, IL scores 68/100 (Grade C). 16 ZIP codes analyzed. 61 EPA violations found. Lead above EPA limits. Free report with contam...

Fulton County, IL: 16 Health Violations — 56/100 (2026)

2026 report: Fulton County, IL scores 56/100 (Grade C). 19 ZIP codes analyzed. 47 EPA violations found. Free report with contaminant data and filter picks.

Gallatin County, IL: 10 Violations — 73/100 (2026)

2026 report: Gallatin County, IL scores 73/100 (Grade B). 7 ZIP codes analyzed. 10 EPA violations found. Free report with contaminant data and filter pi...

Greene County, IL: 4 Health Violations — 59/100 (2026)

2026 report: Greene County, IL scores 59/100 (Grade C). 10 ZIP codes analyzed. 47 EPA violations found. Free report with contaminant data and filter picks.

Grundy County, IL: 7 Health Violations — 56/100 (2026)

2026 report: Grundy County, IL scores 56/100 (Grade C). 11 ZIP codes analyzed. 62 EPA violations found. Free report with contaminant data and filter picks.

Hamilton County, IL: 1 Health Violation — 64/100 (2026)

2026 report: Hamilton County, IL scores 64/100 (Grade C). 6 ZIP codes analyzed. 14 EPA violations found. Free report with contaminant data and filter pi...

Hancock County, IL: Lead Above EPA Limits — 53/100 (2026)

2026 report: Hancock County, IL scores 53/100 (Grade D). 18 ZIP codes analyzed. 39 EPA violations found. Lead above EPA limits. Free report with contami...

Hardin County, IL: Lead Above EPA Limits — 65/100 (2026)

2026 report: Hardin County, IL scores 65/100 (Grade C). 5 ZIP codes analyzed. 1 EPA violation found. Lead above EPA limits. Free report with contaminant...

Henderson County, IL: 14 Violations — 57/100 (2026)

2026 report: Henderson County, IL scores 57/100 (Grade C). 8 ZIP codes analyzed. 14 EPA violations found. Free report with contaminant data and filter p...

Henry County, IL: Lead Above EPA Limits — 58/100 (2026)

2026 report: Henry County, IL scores 58/100 (Grade C). 14 ZIP codes analyzed. 46 EPA violations found. Lead above EPA limits. Free report with contamina...

Iroquois County, IL: Lead Above EPA Limits — 54/100 (2026)

2026 report: Iroquois County, IL scores 54/100 (Grade D). 23 ZIP codes analyzed. 68 EPA violations found. Lead above EPA limits. Free report with contam...

Jackson County, IL: Lead Above EPA Limits — 69/100 (2026)

2026 report: Jackson County, IL scores 69/100 (Grade C). 17 ZIP codes analyzed. 76 EPA violations found. Lead above EPA limits. Free report with contami...

Jasper County, IL: Lead Above EPA Limits — 62/100 (2026)

2026 report: Jasper County, IL scores 62/100 (Grade C). 5 ZIP codes analyzed. 14 EPA violations found. Lead above EPA limits. Free report with contamina...

Jefferson County, IL: 15 Violations — 68/100 (2026)

2026 report: Jefferson County, IL scores 68/100 (Grade C). 14 ZIP codes analyzed. 15 EPA violations found. Free report with contaminant data and filter ...

Jersey County, IL: 4 Health Violations — 56/100 (2026)

2026 report: Jersey County, IL scores 56/100 (Grade C). 9 ZIP codes analyzed. 30 EPA violations found. Free report with contaminant data and filter picks.

Jo Daviess County, IL: 2 Health Violations — 56/100 (2026)

2026 report: Jo Daviess County, IL scores 56/100 (Grade C). 10 ZIP codes analyzed. 20 EPA violations found. Free report with contaminant data and filter...

Johnson County, IL: Lead Above EPA Limits — 64/100 (2026)

2026 report: Johnson County, IL scores 64/100 (Grade C). 11 ZIP codes analyzed. 22 EPA violations found. Lead above EPA limits. Free report with contami...

Kane County, IL: Lead Above EPA Limits — 49/100 (2026)

2026 report: Kane County, IL scores 49/100 (Grade D). 32 ZIP codes analyzed. 144 EPA violations found. Lead above EPA limits. Free report with contamina...

Kankakee County, IL: 7 Health Violations — 67/100 (2026)

2026 report: Kankakee County, IL scores 67/100 (Grade C). 15 ZIP codes analyzed. 69 EPA violations found. Free report with contaminant data and filter p...

Kendall County, IL: 1 Health Violation — 58/100 (2026)

2026 report: Kendall County, IL scores 58/100 (Grade C). 7 ZIP codes analyzed. 16 EPA violations found. Free report with contaminant data and filter picks.

Knox County, IL: 8 Health Violations — 57/100 (2026)

2026 report: Knox County, IL scores 57/100 (Grade C). 20 ZIP codes analyzed. 50 EPA violations found. Free report with contaminant data and filter picks.

Lake County, IL: Lead Above EPA Limits — 63/100 (2026)

2026 report: Lake County, IL scores 63/100 (Grade C). 32 ZIP codes analyzed. 107 EPA violations found. Lead above EPA limits. Free report with contamina...

LaSalle County, IL: Lead Above EPA Limits — 67/100 (2026)

2026 report: LaSalle County, IL scores 67/100 (Grade C). 24 ZIP codes analyzed. 160 EPA violations found. Lead above EPA limits. Free report with contam...

Lawrence County, IL: Lead Above EPA Limits — 61/100 (2026)

2026 report: Lawrence County, IL scores 61/100 (Grade C). 4 ZIP codes analyzed. 28 EPA violations found. Lead above EPA limits. Free report with contami...

Lee County, IL: Lead Above EPA Limits — 53/100 (2026)

2026 report: Lee County, IL scores 53/100 (Grade D). 16 ZIP codes analyzed. 55 EPA violations found. Lead above EPA limits. Free report with contaminant...

Livingston County, IL: Lead Above EPA Limits — 54/100 (2026)

2026 report: Livingston County, IL scores 54/100 (Grade D). 19 ZIP codes analyzed. 64 EPA violations found. Lead above EPA limits. Free report with cont...

Logan County, IL: Lead Above EPA Limits — 52/100 (2026)

2026 report: Logan County, IL scores 52/100 (Grade D). 14 ZIP codes analyzed. 20 EPA violations found. Lead above EPA limits. Free report with contamina...

Macon County, IL: 4 Health Violations — 57/100 (2026)

2026 report: Macon County, IL scores 57/100 (Grade C). 18 ZIP codes analyzed. 48 EPA violations found. Free report with contaminant data and filter picks.

Macoupin County, IL: 35 Health Violations — 71/100 (2026)

2026 report: Macoupin County, IL scores 71/100 (Grade B). 21 ZIP codes analyzed. 114 EPA violations found. Free report with contaminant data and filter ...

Madison County, IL: Lead Above EPA Limits — 69/100 (2026)

2026 report: Madison County, IL scores 69/100 (Grade C). 30 ZIP codes analyzed. 92 EPA violations found. Lead above EPA limits. Free report with contami...

Marion County, IL: 32 Violations — 79/100 (2026)

2026 report: Marion County, IL scores 79/100 (Grade B). 8 ZIP codes analyzed. 32 EPA violations found. Free report with contaminant data and filter picks.

Marshall County, IL: 1 Health Violation — 61/100 (2026)

2026 report: Marshall County, IL scores 61/100 (Grade C). 9 ZIP codes analyzed. 5 EPA violations found. Free report with contaminant data and filter picks.

Mason County, IL: Lead Above EPA Limits — 53/100 (2026)

2026 report: Mason County, IL scores 53/100 (Grade D). 7 ZIP codes analyzed. 10 EPA violations found. Lead above EPA limits. Free report with contaminan...

Massac County, IL: 3 Health Violations — 81/100 (2026)

2026 report: Massac County, IL scores 81/100 (Grade B). 3 ZIP codes analyzed. 10 EPA violations found. Free report with contaminant data and filter picks.

McDonough County, IL: Lead Above EPA Limits — 56/100 (2026)

2026 report: McDonough County, IL scores 56/100 (Grade C). 11 ZIP codes analyzed. 13 EPA violations found. Lead above EPA limits. Free report with conta...

McHenry County, IL: Lead Above EPA Limits — 68/100 (2026)

2026 report: McHenry County, IL scores 68/100 (Grade C). 21 ZIP codes analyzed. 43 EPA violations found. Lead above EPA limits. Free report with contami...

McLean County, IL: Lead Above EPA Limits — 57/100 (2026)

2026 report: McLean County, IL scores 57/100 (Grade C). 30 ZIP codes analyzed. 295 EPA violations found. Lead above EPA limits. Free report with contami...

Menard County, IL: 3 Health Violations — 59/100 (2026)

2026 report: Menard County, IL scores 59/100 (Grade C). 7 ZIP codes analyzed. 20 EPA violations found. Free report with contaminant data and filter picks.

Mercer County, IL: 1 Health Violation — 58/100 (2026)

2026 report: Mercer County, IL scores 58/100 (Grade C). 13 ZIP codes analyzed. 29 EPA violations found. Free report with contaminant data and filter picks.

Monroe County, IL: 2 Health Violations — 68/100 (2026)

2026 report: Monroe County, IL scores 68/100 (Grade C). 5 ZIP codes analyzed. 18 EPA violations found. Free report with contaminant data and filter picks.

Montgomery County, IL: 9 Health Violations — 70/100 (2026)

2026 report: Montgomery County, IL scores 70/100 (Grade B). 16 ZIP codes analyzed. 60 EPA violations found. Free report with contaminant data and filter...

Morgan County, IL: 15 Health Violations — 56/100 (2026)

2026 report: Morgan County, IL scores 56/100 (Grade C). 10 ZIP codes analyzed. 35 EPA violations found. Free report with contaminant data and filter picks.

Moultrie County, IL: Lead Above EPA Limits — 53/100 (2026)

2026 report: Moultrie County, IL scores 53/100 (Grade D). 4 ZIP codes analyzed. 5 EPA violations found. Lead above EPA limits. Free report with contamin...

Ogle County, IL: 1 Health Violation — 55/100 (2026)

2026 report: Ogle County, IL scores 55/100 (Grade C). 16 ZIP codes analyzed. 25 EPA violations found. Free report with contaminant data and filter picks.

Peoria County, IL: Lead Above EPA Limits — 37/100 (2026)

2026 report: Peoria County, IL scores 37/100 (Grade F). 40 ZIP codes analyzed. 229 EPA violations found. Lead above EPA limits. Free report with contami...

Perry County, IL: 6 Health Violations — 74/100 (2026)

2026 report: Perry County, IL scores 74/100 (Grade B). 5 ZIP codes analyzed. 21 EPA violations found. Free report with contaminant data and filter picks.

Piatt County, IL: 3 Health Violations — 60/100 (2026)

2026 report: Piatt County, IL scores 60/100 (Grade C). 11 ZIP codes analyzed. 25 EPA violations found. Free report with contaminant data and filter picks.

Pike County, IL: 1 Health Violation — 61/100 (2026)

2026 report: Pike County, IL scores 61/100 (Grade C). 15 ZIP codes analyzed. 45 EPA violations found. Free report with contaminant data and filter picks.

Pope County, IL: 3 Health Violations — 55/100 (2026)

2026 report: Pope County, IL scores 55/100 (Grade C). 2 ZIP codes analyzed. 3 EPA violations found. Free report with contaminant data and filter picks.

Pulaski County, IL: Lead Above EPA Limits — 79/100 (2026)

2026 report: Pulaski County, IL scores 79/100 (Grade B). 9 ZIP codes analyzed. 21 EPA violations found. Lead above EPA limits. Free report with contamin...

Putnam County, IL: 1 Health Violation — 62/100 (2026)

2026 report: Putnam County, IL scores 62/100 (Grade C). 7 ZIP codes analyzed. 7 EPA violations found. Free report with contaminant data and filter picks.

Randolph County, IL: Lead Above EPA Limits — 66/100 (2026)

2026 report: Randolph County, IL scores 66/100 (Grade C). 17 ZIP codes analyzed. 74 EPA violations found. Lead above EPA limits. Free report with contam...

Richland County, IL: 3 Health Violations — 72/100 (2026)

2026 report: Richland County, IL scores 72/100 (Grade B). 8 ZIP codes analyzed. 119 EPA violations found. Free report with contaminant data and filter p...

Rock Island County, IL: 10 Health Violations — 54/100 (2026)

2026 report: Rock Island County, IL scores 54/100 (Grade D). 21 ZIP codes analyzed. 123 EPA violations found. Free report with contaminant data and filt...

Saline County, IL: 4 Health Violations — 76/100 (2026)

2026 report: Saline County, IL scores 76/100 (Grade B). 7 ZIP codes analyzed. 35 EPA violations found. Free report with contaminant data and filter picks.

Sangamon County, IL: Lead Above EPA Limits — 53/100 (2026)

2026 report: Sangamon County, IL scores 53/100 (Grade D). 56 ZIP codes analyzed. 405 EPA violations found. Lead above EPA limits. Free report with conta...

Schuyler County, IL: 2 Health Violations — 58/100 (2026)

2026 report: Schuyler County, IL scores 58/100 (Grade C). 4 ZIP codes analyzed. 9 EPA violations found. Free report with contaminant data and filter picks.

Scott County, IL: 3 Health Violations — 61/100 (2026)

2026 report: Scott County, IL scores 61/100 (Grade C). 5 ZIP codes analyzed. 12 EPA violations found. Free report with contaminant data and filter picks.

Shelby County, IL: 6 Health Violations — 71/100 (2026)

2026 report: Shelby County, IL scores 71/100 (Grade B). 13 ZIP codes analyzed. 47 EPA violations found. Free report with contaminant data and filter picks.

St. Clair County, IL: 10 Health Violations — 68/100 (2026)

2026 report: St. Clair County, IL scores 68/100 (Grade C). 30 ZIP codes analyzed. 102 EPA violations found. Free report with contaminant data and filter...

Stark County, IL: 2 Health Violations — 56/100 (2026)

2026 report: Stark County, IL scores 56/100 (Grade C). 5 ZIP codes analyzed. 12 EPA violations found. Free report with contaminant data and filter picks.

Stephenson County, IL: Lead Above EPA Limits — 53/100 (2026)

2026 report: Stephenson County, IL scores 53/100 (Grade D). 14 ZIP codes analyzed. 57 EPA violations found. Lead above EPA limits. Free report with cont...

Tazewell County, IL: Lead Above EPA Limits — 60/100 (2026)

2026 report: Tazewell County, IL scores 60/100 (Grade C). 20 ZIP codes analyzed. 100 EPA violations found. Lead above EPA limits. Free report with conta...

Union County, IL: 6 Health Violations — 70/100 (2026)

2026 report: Union County, IL scores 70/100 (Grade B). 7 ZIP codes analyzed. 14 EPA violations found. Free report with contaminant data and filter picks.

Vermilion County, IL: Lead Above EPA Limits — 57/100 (2026)

2026 report: Vermilion County, IL scores 57/100 (Grade C). 23 ZIP codes analyzed. 63 EPA violations found. Lead above EPA limits. Free report with conta...

Wabash County, IL: 1 Health Violation — 77/100 (2026)

2026 report: Wabash County, IL scores 77/100 (Grade B). 5 ZIP codes analyzed. 7 EPA violations found. Free report with contaminant data and filter picks.

Warren County, IL: Lead Above EPA Limits — 56/100 (2026)

2026 report: Warren County, IL scores 56/100 (Grade C). 6 ZIP codes analyzed. 18 EPA violations found. Lead above EPA limits. Free report with contamina...

Washington County, IL: 4 Health Violations — 69/100 (2026)

2026 report: Washington County, IL scores 69/100 (Grade C). 9 ZIP codes analyzed. 19 EPA violations found. Free report with contaminant data and filter ...

Wayne County, IL: 8 Health Violations — 63/100 (2026)

2026 report: Wayne County, IL scores 63/100 (Grade C). 9 ZIP codes analyzed. 36 EPA violations found. Free report with contaminant data and filter picks.

White County, IL: 9 Violations — 71/100 (2026)

2026 report: White County, IL scores 71/100 (Grade B). 8 ZIP codes analyzed. 9 EPA violations found. Free report with contaminant data and filter picks.

Whiteside County, IL: 5 Health Violations — 54/100 (2026)

2026 report: Whiteside County, IL scores 54/100 (Grade D). 13 ZIP codes analyzed. 56 EPA violations found. Free report with contaminant data and filter ...

Will County, IL: Lead Above EPA Limits — 66/100 (2026)

2026 report: Will County, IL scores 66/100 (Grade C). 27 ZIP codes analyzed. 421 EPA violations found. Lead above EPA limits. Free report with contamina...

Williamson County, IL: Lead Above EPA Limits — 72/100 (2026)

2026 report: Williamson County, IL scores 72/100 (Grade B). 10 ZIP codes analyzed. 48 EPA violations found. Lead above EPA limits. Free report with cont...

Winnebago County, IL: 22 Health Violations — 47/100 (2026)

2026 report: Winnebago County, IL scores 47/100 (Grade D). 28 ZIP codes analyzed. 207 EPA violations found. Free report with contaminant data and filter...

Woodford County, IL: Lead Above EPA Limits — 60/100 (2026)

2026 report: Woodford County, IL scores 60/100 (Grade C). 13 ZIP codes analyzed. 67 EPA violations found. Lead above EPA limits. Free report with contam...