Data report · 2026

South Carolina Water Damage Risk Index

Where in South Carolina is a house most likely to take on water? We combined Census housing age with ten years of daily weather for 46 of South Carolina's 46 counties to rank them.

Highest index

Newberry

Score 74 of 100

Most pipe-freeze nights

Cherokee

5 nights ≤ 20°F a year

Oldest housing

Union

31% built before 1960

Most heavy-rain days

Oconee

15.8 days ≥ 1 inch a year

< 3939–4646–5656–60≥ 60 index (0–100)

Key findings

The five highest-scoring counties are Newberry, Allendale, Aiken, Bamberg, Barnwell. Each combines old housing with harsher-than-average winters or frequent downpours.
Union County has the oldest housing in the state, with 31% of homes built before 1960, against a county median of 15%.
Cherokee County averaged 5 nights a year at 20°F or colder, the most of any county in the data. The county median is 2.
Jasper County has the newest housing, with 57% of homes built since 2000, which pulls its index down even where winters are cold.

Weather: NOAA nClimGrid-Daily county averages, 2015–2024. Housing: ACS 2020-2024.

All counties

Select a column header to sort.

Rank	County	Index	Freeze nights	Pre-1960 homes	Heavy-rain days	Muggy nights
1	Newberry	74	3	27%	12.7	103
2	Allendale	70	2	24%	13.5	118
3	Aiken	64	2	18%	13.7	115
4	Bamberg	63	2	25%	12.4	117
5	Barnwell	63	2	18%	13.4	115
6	Greenville	62	4	13%	15.1	94
7	Pickens	62	4	13%	15.5	91
8	Darlington	61	3	18%	11.2	114
9	Marion	60	2	21%	12.2	118
10	Oconee	60	4	12%	15.8	83
11	Spartanburg	60	3	16%	12.5	96
12	Abbeville	59	2	24%	12.6	106
13	Anderson	59	3	15%	12.8	101
14	Chester	59	3	26%	11	95
15	Greenwood	58	2	25%	12.4	105
16	Marlboro	58	3	25%	10.3	113
17	Union	58	3	31%	10.6	96
18	Hampton	56	1	17%	12.8	126
19	McCormick	56	2	18%	12.5	109
20	Saluda	56	2	20%	12.5	105
21	Laurens	55	3	16%	12.1	101
22	Fairfield	54	3	16%	11.4	103
23	Calhoun	52	2	16%	11.2	120
24	Chesterfield	52	3	16%	11.1	105
25	Dillon	52	3	16%	10.8	116
26	Georgetown	51	2	8%	14.1	121
27	Charleston	48	0	15%	12.9	140
28	Cherokee	46	5	15%	10.3	86
29	Lee	46	3	15%	10.7	114
30	Horry	45	2	4%	12.8	120
31	Orangeburg	45	2	15%	11	119
32	Colleton	44	1	14%	12.6	129
33	Edgefield	42	2	14%	12.2	112
34	Lancaster	41	4	14%	10.3	94
35	Richland	40	2	16%	10.9	113
36	Williamsburg	40	2	14%	11.2	117
37	Florence	39	2	15%	10.6	118
38	Berkeley	38	1	4%	13.3	126
39	York	35	4	9%	10.1	89
40	Clarendon	34	2	9%	11	118
41	Jasper	34	1	5%	12.3	136
42	Kershaw	34	3	11%	9.3	106
43	Lexington	33	2	8%	12.1	110
44	Dorchester	28	1	4%	11.7	128
45	Sumter	28	2	12%	10	117
46	Beaufort	26	0	4%	11.9	152

Methodology

For each county with weather data, we convert four factors to a percentile rank among those counties (0 = lowest, 100 = highest), then take a weighted average:

Pipe-freeze nights (nights ≤ 20°F / yr), weight 30%
Homes built before 1960 (% of homes), weight 30%
Heavy-rain days (days ≥ 1 in / yr), weight 25%
Muggy nights (nights ≥ 65°F / yr), weight 15%

Freezing weather and old plumbing get the most weight because burst and failing supply lines are among the most common causes of household water damage. Heavy rain drives basement flooding and sewer backups, and warm, muggy nights mark the humid air that lets mold follow. The index is relative: a low score means lower risk than other South Carolina counties, not no risk.

Limits: weather values are county-wide averages, so hollows, ridges and lakeshores can differ; ACS housing figures are survey estimates; the index doesn't account for floodplains, soil, or local sewer systems. Full details on our data sources page.

Cite this data

You're welcome to use these figures with attribution. Suggested citation:

Local Water & Mold, "South Carolina Water Damage Risk Index 2026," https://localwatermold.com/south-carolina/south-carolina-water-damage-risk/. Data: U.S. Census Bureau ACS 2020-2024; NOAA nClimGrid-Daily 2015–2024.