countyscore

Best Water Quality Counties in South Carolina

EPA drinking water health violations and safety grades Compare rankings across all 46 counties.

Average Water Quality Score
65/100
Top County
Allendale County
Counties Ranked
46

Top 10

#1
Allendale County
SC
86/100
#2
Barnwell County
SC
86/100
#3
Calhoun County
SC
86/100
#4
Chester County
SC
86/100
#5
Clarendon County
SC
86/100
#6
Darlington County
SC
86/100
#7
Dillon County
SC
86/100
#8
Edgefield County
SC
86/100
#9
Florence County
SC
86/100
#10
Hampton County
SC
86/100

All South Carolina Counties Ranked

#CountyWater Quality ScoreOverall Score
1Allendale County, SC
86
43.9
2Barnwell County, SC
86
39.8
3Calhoun County, SC
86
47.8
4Chester County, SC
86
40.3
5Clarendon County, SC
86
42.6
6Darlington County, SC
86
44.9
7Dillon County, SC
86
40.3
8Edgefield County, SC
86
59
9Florence County, SC
86
39.5
10Hampton County, SC
86
39.2
11Jasper County, SC
86
34.6
12Kershaw County, SC
86
42.5
13Lancaster County, SC
86
44.8
14Lee County, SC
86
43.9
15Marion County, SC
86
46.2
16Marlboro County, SC
86
39.8
17Orangeburg County, SC
86
36.4
18Greenville County, SC
71.8
40.8
19Spartanburg County, SC
71.5
40.3
20Anderson County, SC
71.1
40.9
21Horry County, SC
68.4
39.4
22Laurens County, SC
68.4
43.8
23Greenwood County, SC
68.2
39
24Oconee County, SC
67.8
48
25Richland County, SC
64.8
36.7
26Sumter County, SC
64.8
35.2
27Newberry County, SC
63.8
43.4
28Charleston County, SC
63.2
43.4
29Pickens County, SC
63
50.4
30Dorchester County, SC
62.3
48.5
31York County, SC
61.3
44.5
32Beaufort County, SC
59.3
45.5
33Aiken County, SC
59.2
44.5
34Fairfield County, SC
56
45.3
35Lexington County, SC
53.8
38.3
36Georgetown County, SC
52.7
41.8
37Berkeley County, SC
51.4
35.1
38Colleton County, SC
50.1
31.7
39Cherokee County, SC
43.7
44.8
40Bamberg County, SC
38
39.5
41Chesterfield County, SC
28.8
43.2
42Abbeville County, SC
26.8
51
43Williamsburg County, SC
25.4
39.3
44Saluda County, SC
24.2
50.1
45McCormick County, SC
12.8
59.4
46Union County, SC
12.3
38.6

Data Source

Water Quality data from WaterByCounty. See full details at WaterByCounty. Data updated February 2026.