Clinton County, Ohio
A shallow water table limits basements on 93% of Clinton County's mapped land, a higher share than 98% of US counties. Shrink-swell clay limits houses without basements on 16%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 9 flood losses here since 2016. 53% of homes were built before 1980, against 50% nationally; the median home dates from 1977.
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 Clinton County
| Expansive clay (limits slab homes) | 16.1% |
| High water table (limits basements) | 93.0% |
| Septic fields very limited | 95.5% |
| Clay swell (LEP, by area) | 4.5% |
| High-swell land (LEP 6%+) | 4.3% |
| Mapped soil | 263,885 acres |
How we count · survey areas OH027 (2025-08-27)
What the numbers mean here
Clay swell averages a linear extensibility of 4.5% by land area here, and 4% 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.
On 93% of Clinton 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: 48.34 in, 4.61 in above the 1991-2020 average year of 43.73 in.
USDA rates 95% 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
9 flood losses since 2016, $174,810 paid. The worst year was 2025, with 4.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 1 |
| 2018 | 0 |
| 2019 | 1 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 3 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 4 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 43.73 in |
| 12 months to August 2026 | 48.34 in (+4.61) |
| 2025 | 46.12 in (+2.39) |
| Wettest year since 1895 | 2011: 58.46 in |
| Driest year since 1895 | 1930: 26.76 in |
| Days with 1 inch or more, normal at WFO WILMINGTON (1 mi away) | 10.2 |
Homes
| Housing units | 18,039 |
| Median year built | 1977 |
| Built before 1980 | 53% |
| Built 2000 or later | 19% |
| Owner-occupied | 72% |
| Median value, owner-occupied | $211,900 |
| Single-family detached | 78% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Clinton County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Blanchester | 1% | 94% | 1,890 |
| Clarksville | 0% | 41% | 344 |
| Martinsville | 5% | 79% | 154 |
| Midland | 1% | 100% | 169 |
| New Vienna | 10% | 73% | 504 |
| Port William | 2% | 79% | 86 |
| Sabina | 39% | 98% | 1,264 |
| Wilmington | 15% | 93% | 5,943 |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Greene County, OH | 19 mi | 8% | 68% |
| Highland County, OH | 20 mi | 3% | 66% |
| Fayette County, OH | 20 mi | 37% | 96% |
| Warren County, OH | 20 mi | 10% | 51% |
| Clermont County, OH | 32 mi | 8% | 67% |
| Clark County, OH | 34 mi | 17% | 59% |
| Brown County, OH | 35 mi | 11% | 68% |
| Montgomery County, OH | 35 mi | 17% | 65% |
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