PlainWater
States

Ohio Water Quality

4,181 public water systems serving 11,085,226 people.

Water Systems
4,181
Total Violations
288,388
Violation Rate
90.4%
PFAS Detection
59%
204 of 346 tested

Largest Water Systems

Most Violations

Counties in Ohio

Franklin
96 systems · 1,503,985 served · 5,342 violations
Cuyahoga
11 systems · 1,410,751 served · 1,166 violations
Hamilton
28 systems · 842,267 served · 1,480 violations
Montgomery
74 systems · 529,379 served · 4,724 violations
Summit
214 systems · 467,695 served · 17,163 violations
Lucas
46 systems · 433,198 served · 3,569 violations
Butler
22 systems · 378,755 served · 1,035 violations
Lorain
17 systems · 330,150 served · 1,534 violations
Stark
182 systems · 314,229 served · 12,064 violations
Warren
21 systems · 242,137 served · 4,221 violations
Lake
20 systems · 230,589 served · 1,095 violations
Mahoning
75 systems · 228,296 served · 4,611 violations
Delaware
5 systems · 195,368 served · 521 violations
Clermont
9 systems · 187,400 served · 1,204 violations
Greene
56 systems · 180,062 served · 3,157 violations
Trumbull
89 systems · 160,312 served · 6,699 violations
Licking
88 systems · 129,554 served · 6,135 violations
Portage
173 systems · 127,607 served · 9,333 violations
Wood
55 systems · 116,066 served · 3,536 violations
Medina
63 systems · 115,354 served · 3,445 violations
Clark
92 systems · 106,745 served · 9,196 violations
Richland
121 systems · 103,898 served · 6,673 violations
Fairfield
75 systems · 100,143 served · 6,414 violations
Miami
57 systems · 94,299 served · 4,277 violations
Allen
41 systems · 90,674 served · 3,083 violations
Ashtabula
57 systems · 87,422 served · 3,578 violations
Wayne
177 systems · 85,031 served · 10,471 violations
Scioto
17 systems · 83,235 served · 348 violations
Erie
13 systems · 80,465 served · 980 violations
Athens
13 systems · 75,476 served · 1,430 violations

Showing top 30 of 88 counties.