HomeWest VirginiaMason County

Mason County, West Virginia

Shrink-swell clay limits houses without basements on 32% of Mason County's mapped land, a higher share than 82% of US counties. A shallow water table limits basements on 16%.

None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 11 flood losses here since 2016. 52% of homes were built before 1980, against 50% nationally; the median home dates from 1978.

Data as of October 13, 2026 · sources

32%

expansive clay: shrink-swell limits slab homes

16%

high water table: limits basements

0%

in drought, October 13, 2026

52%

of homes built before 1980

Soil under Mason County

Expansive clay (limits slab homes)31.7%
High water table (limits basements)15.6%
Septic fields very limited93.0%
Clay swell (LEP, by area)3.8%
High-swell land (LEP 6%+)20.9%
Mapped soil284,900 acres
Soil seriesShare hereSeries nationally: expansive clay
Gilpin35%0%
Upshur19%99%
Peabody12%n/a
Vandalia5%n/a
Sensabaugh3%n/a
Melvin2%n/a
Gallia County: 29%Putnam County: 33%Jackson County: 47%Meigs County: 43%Cabell County: 21%Lawrence County: 29%Jackson County: 17%Roane County: 36%Mason County GalliaPutnamJacksonMeigsCabellLawrenceJacksonRoaneMason
Mason County (heavy outline) and nearby counties, shaded by expansive clay share.under 10%10-25%25-40%40-60%60%+

How we count · survey areas WV600 (2025-09-08)

What the numbers mean here

Clay swell averages a linear extensibility of 3.8% by land area here, and 21% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 32% of the mapped land.

On 16% of Mason 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: 42.11 in, 2.08 in below the 1991-2020 average year of 44.19 in.

USDA rates 93% of the land very limited for septic absorption fields.

Drought

0% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 8 of the last 52 weeks; the most was 100% of its area, on the May 19, 2026 map.

October 21, 2025Share of area in drought, weeklyOctober 13, 2026
Category, October 13, 2026Share of county
D0 abnormally dry or worse0%
D1 moderate drought or worse0%
D2 severe or worse0%
D3 extreme or worse0%
D4 exceptional0%

Flood losses since 2016

11 flood losses since 2016, $253,504 paid. The worst year was 2018, with 3.

YearFlood losses
20160
20170
20183
20192
20202
20212
20221
20230
20240
20251
2026 to date0

Rain

Average year, 1991-202044.19 in
12 months to August 202642.11 in (-2.08)
202546.89 in (+2.70)
Wettest year since 18952011: 57.09 in
Driest year since 18951930: 24.42 in
Days with 1 inch or more, normal at GALLIPOLIS (9 mi away)9.8

Homes

Housing units12,179
Median year built1978
Built before 198052%
Built 2000 or later22%
Owner-occupied82%
Median value, owner-occupied$120,300
Single-family detached67%

What repairs cost

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

WorkRangeSource
Foundation repair, US $2,200 to $8,200 Fixr, January 27, 2026
Pier-and-beam repair, US $2,000 to $15,000 Fixr, January 27, 2026
Foundation inspection, US $300 to $600 Fixr, January 31, 2025

Nearby counties

PlaceDistanceExpansive clayHigh water table
Gallia County, OH 15 mi 29% 26%
Putnam County, WV 19 mi 33% 9%
Jackson County, WV 19 mi 47% 9%
Meigs County, OH 22 mi 43% 21%
Cabell County, WV 27 mi 21% 11%
Lawrence County, OH 29 mi 29% 11%
Jackson County, OH 36 mi 17% 53%
Roane County, WV 36 mi 36% 6%

Sources: USDA SSURGO (September 8, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status