Washington County, Ohio
A shallow water table limits basements on 19% of Washington County's mapped land. Shrink-swell clay limits houses without basements on 40%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 64 flood losses here since 2016, 23% of them in buildings with basements. 63% of homes were built before 1980, against 50% nationally; the median home dates from 1973.
Data as of October 13, 2026 · sources
expansive clay: shrink-swell limits slab homes
high water table: limits basements
in drought, October 13, 2026
of homes built before 1980
Soil under Washington County
| Expansive clay (limits slab homes) | 39.7% |
| High water table (limits basements) | 18.9% |
| Septic fields very limited | 95.5% |
| Clay swell (LEP, by area) | 4.6% |
| High-swell land (LEP 6%+) | 38.9% |
| Mapped soil | 409,408 acres |
How we count · survey areas OH167 (2025-09-08)
What the numbers mean here
Clay swell averages a linear extensibility of 4.6% by land area here, and 39% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 40% of the mapped land.
On 19% of Washington 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: 46.89 in, 2.83 in above the 1991-2020 average year of 44.06 in.
USDA rates 96% 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. No part of the county was in drought in the last 52 weeks.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 0% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
64 flood losses since 2016, $1.2 million paid. The worst year was 2018, with 23. Foundations of the buildings, where recorded: 23% basements, 51% slabs, 6% crawl spaces, 19% elevated. Median water depth outside the building: 28 in.
| Year | Flood losses |
|---|---|
| 2016 | 1 |
| 2017 | 2 |
| 2018 | 23 |
| 2019 | 3 |
| 2020 | 0 |
| 2021 | 1 |
| 2022 | 2 |
| 2023 | 4 |
| 2024 | 21 |
| 2025 | 0 |
| 2026 to date | 7 |
Rain
| Average year, 1991-2020 | 44.06 in |
| 12 months to August 2026 | 46.89 in (+2.83) |
| 2025 | 44.29 in (+0.23) |
| Wettest year since 1895 | 2018: 62.71 in |
| Driest year since 1895 | 1930: 22.31 in |
| Days with 1 inch or more, normal at MARIETTA WWTP (4 mi away) | 9.5 |
Homes
| Housing units | 27,949 |
| Median year built | 1973 |
| Built before 1980 | 63% |
| Built 2000 or later | 14% |
| Owner-occupied | 75% |
| Median value, owner-occupied | $185,600 |
| Single-family detached | 78% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Washington County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Belpre | 19% | 8% | 3,385 |
| Beverly | 2% | 7% | 607 |
| Lowell | 5% | 13% | 289 |
| Lower Salem | 4% | 6% | 38 |
| Macksburg | 10% | 22% | 71 |
| Marietta | 40% | 15% | 6,852 |
| Matamoras (New Matamoras) | under 1% | 21% | 460 |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Wood County, WV | 16 mi | 45% | 21% |
| Pleasants County, WV | 18 mi | 32% | 5% |
| Noble County, OH | 22 mi | 31% | 18% |
| Morgan County, OH | 23 mi | 35% | 23% |
| Monroe County, OH | 29 mi | 27% | 18% |
| Ritchie County, WV | 30 mi | 44% | 10% |
| Wirt County, WV | 30 mi | 50% | 17% |
| Athens County, OH | 31 mi | 29% | 27% |
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