Illinois County Drinking Water Report Cards
Compare county Drinking Water Violation Exposure Scores in Illinois. Scores combine health-based violations per 100,000 people served and the share of active systems with unresolved health-based violations. View methodology or download the CSV.
| Score | Grade | County | Systems | Population | Health Violations | Per 100K | Active Health Systems |
|---|---|---|---|---|---|---|---|
| 0 | F | Bureau County | 22 | 25,476 | 93 | 365.0 | 7 |
| 0 | F | Christian County | 11 | 26,251 | 38 | 144.8 | 3 |
| 0 | F | Williamson County | 18 | 63,786 | 32 | 50.2 | 5 |
| 0 | F | Grundy County | 12 | 40,806 | 27 | 66.2 | 3 |
| 0 | F | Jackson County | 13 | 41,049 | 25 | 60.9 | 3 |
| 0 | F | Knox County | 14 | 43,667 | 13 | 29.8 | 3 |
| 0 | F | Whiteside County | 12 | 37,135 | 9 | 24.2 | 5 |
| 5 | F | Woodford County | 17 | 25,204 | 39 | 154.7 | 3 |
| 5 | F | Vermilion County | 17 | 54,184 | 9 | 16.6 | 3 |
| 7 | F | Randolph County | 12 | 24,243 | 42 | 173.2 | 2 |
| 7 | F | Rock Island County | 18 | 131,795 | 29 | 22.0 | 3 |
| 9 | F | Macon County | 13 | 102,990 | 30 | 29.1 | 2 |
| 9 | F | Montgomery County | 13 | 13,783 | 18 | 130.6 | 2 |
| 10 | F | Macoupin County | 20 | 32,203 | 56 | 173.9 | 3 |
| 11 | F | Lasalle County | 21 | 82,967 | 44 | 53.0 | 3 |
| 11 | F | Iroquois County | 21 | 19,353 | 38 | 196.4 | 3 |
| 11 | F | Henry County | 14 | 34,551 | 10 | 28.9 | 2 |
| 13 | F | Winnebago County | 22 | 239,341 | 30 | 12.5 | 3 |
| 13 | F | Livingston County | 15 | 28,388 | 19 | 66.9 | 2 |
| 18 | F | Mclean County | 27 | 161,325 | 159 | 98.6 | 3 |
| 20 | F | Wayne County | 10 | 16,144 | 31 | 192.0 | 1 |
| 20 | F | Hancock County | 10 | 9,468 | 20 | 211.2 | 1 |
| 20 | F | Ford County | 10 | 10,804 | 7 | 64.8 | 1 |
| 20 | F | Stephenson County | 10 | 31,058 | 6 | 19.3 | 1 |
| 20 | F | Mercer County | 10 | 8,739 | 4 | 45.8 | 1 |
| 22 | F | Will County | 44 | 559,590 | 31 | 5.5 | 4 |
| 22 | F | Tazewell County | 22 | 111,017 | 19 | 17.1 | 2 |
| 23 | F | Lee County | 12 | 22,084 | 49 | 221.9 | 1 |
| 23 | F | Adams County | 12 | 48,002 | 28 | 58.3 | 1 |
| 23 | F | Ogle County | 12 | 30,060 | 21 | 69.9 | 1 |
| 27 | F | Clinton County | 15 | 27,832 | 24 | 86.2 | 1 |
| 27 | F | Madison County | 31 | 235,394 | 14 | 5.9 | 2 |
| 29 | F | Lake County | 56 | 580,576 | 44 | 7.6 | 3 |
| 39 | F | Cook County | 132 | 2,419,792 | 114 | 4.7 | 3 |
| 40 | F | Mcdonough County | 12 | 25,100 | 62 | 247.0 | 0 |
| 40 | F | Fulton County | 15 | 29,141 | 60 | 205.9 | 0 |
| 40 | F | Sangamon County | 37 | 177,692 | 42 | 23.6 | 0 |
| 40 | F | Effingham County | 10 | 22,406 | 37 | 165.1 | 0 |
| 40 | F | St. Clair County | 23 | 246,484 | 34 | 13.8 | 0 |
| 40 | F | Dekalb County | 14 | 90,920 | 21 | 23.1 | 0 |
| 40 | F | Champaign County | 27 | 198,585 | 15 | 7.6 | 0 |
| 40 | F | Marion County | 11 | 29,227 | 4 | 13.7 | 0 |
| 40 | F | Washington County | 12 | 20,471 | 3 | 14.7 | 0 |
| 41 | F | Mchenry County | 15 | 225,235 | 11 | 4.9 | 0 |
| 47 | F | Franklin County | 15 | 30,248 | 1 | 3.3 | 1 |
| 51 | F | Kane County | 22 | 549,367 | 14 | 2.5 | 2 |
| 62 | D | Peoria County | 12 | 159,188 | 5 | 3.1 | 0 |
| 97 | A | Dupage County | 32 | 814,886 | 2 | 0.2 | 0 |