Orange County, North Carolina

A shallow water table limits basements on 20% of Orange County's mapped land. Shrink-swell clay limits houses without basements on 16%.

100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 304 flood losses here since 2016, 8% of them in buildings with basements. 32% of homes were built before 1980, against 50% nationally; the median home dates from 1990.

Data as of October 13, 2026 · sources

16%

expansive clay: shrink-swell limits slab homes

20%

high water table: limits basements

100%

in drought, October 13, 2026

32%

of homes built before 1980

Soil under Orange County

Expansive clay (limits slab homes)	15.6%
High water table (limits basements)	19.9%
Septic fields very limited	35.9%
Clay swell (LEP, by area)	3.6%
High-swell land (LEP 6%+)	15.9%
Mapped soil	256,646 acres

Soil series	Share here	Series nationally: high water table
Georgeville	29%	0%
Herndon	14%	n/a
Tarrus	10%	n/a
Appling	8%	0%
Helena	6%	n/a
Enon	5%	n/a

Orange County (heavy outline) and nearby counties, shaded by high water table share.under 10%10-25%25-40%40-60%60%+

How we count · survey areas NC135 (2025-08-27)

What the numbers mean here

Clay swell averages a linear extensibility of 3.6% by land area here, and 16% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 16% of the mapped land.

Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 16% of Orange County's mapped land has shrink-swell clay.

On 20% of Orange County's mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.

Rain over the 12 months to August 2026: 30.58 in, 16.32 in below the 1991-2020 average year of 46.90 in.

Drought

100% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 52 of the last 52 weeks; the most was 100% of its area, in 50 weeks, most recently on the October 13, 2026 map.

October 21, 2025Share of area in drought, weeklyOctober 13, 2026

Category, October 13, 2026	Share of county
D0 abnormally dry or worse	100%
D1 moderate drought or worse	100%
D2 severe or worse	34.4%
D3 extreme or worse	0%
D4 exceptional	0%

Flood losses since 2016

304 flood losses since 2016, $28.1 million paid. The worst year was 2025, with 177. Foundations of the buildings, where recorded: 8% basements, 43% slabs, 30% crawl spaces, 20% elevated. Median water depth outside the building: 22 in.

Year	Flood losses
2016	15
2017	1
2018	89
2019	9
2020	1
2021	0
2022	2
2023	2
2024	8
2025	177
2026 to date	0

Rain

Average year, 1991-2020	46.90 in
12 months to August 2026	30.58 in (-16.32)
2025	48.55 in (+1.65)
Wettest year since 1895	2018: 67.79 in
Driest year since 1895	1941: 27.50 in
Days with 1 inch or more, normal at CHAPEL HILL 2 W (11 mi away)	13.2

Homes

Housing units	62,858
Median year built	1990
Built before 1980	32%
Built 2000 or later	33%
Owner-occupied	64%
Median value, owner-occupied	$459,500
Single-family detached	59%

What repairs cost

Published ranges from cost guides, not quotes. More sources, and where they disagree.

Work	Range	Source
Basement waterproofing, US	$3,000 to $10,000	Fixr, February 6, 2026
Sump pump installation, US	$800 to $2,000	Fixr, January 31, 2025
Crawl space encapsulation, US	$2,000 to $8,000	Fixr, August 29, 2025

Nearby counties

Place	Distance	Expansive clay	High water table
Durham County, NC	14 mi	43%	56%
Alamance County, NC	16 mi	20%	24%
Person County, NC	24 mi	18%	29%
Chatham County, NC	26 mi	14%	44%
Caswell County, NC	26 mi	35%	21%
Granville County, NC	31 mi	26%	35%
Wake County, NC	32 mi	4%	32%
Guilford County, NC	37 mi	35%	9%

Sources: USDA SSURGO (August 27, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status