McLean County, Kentucky
A shallow water table limits basements on 81% of McLean County's mapped land, a higher share than 89% of US counties and the highest of 120 Kentucky counties. Shrink-swell clay limits houses without basements on 16%.
7.2% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 29 flood losses here since 2016, 8% of them in buildings with basements. 57% of homes were built before 1980, against 50% nationally; the median home dates from 1976.
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 McLean County
| Expansive clay (limits slab homes) | 16.3% |
| High water table (limits basements) | 80.9% |
| Septic fields very limited | 94.4% |
| Clay swell (LEP, by area) | 3.1% |
| High-swell land (LEP 6%+) | 10.9% |
| Mapped soil | 164,045 acres |
How we count · survey areas KY631 (2025-09-08)
What the numbers mean here
Clay swell averages a linear extensibility of 3.1% by land area here, and 11% 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: 7.2% of the county is in drought on the latest map, and 16% of McLean County's mapped land has shrink-swell clay.
On 81% of McLean 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: 44.24 in, 3.62 in below the 1991-2020 average year of 47.86 in.
USDA rates 94% of the land very limited for septic absorption fields.
Drought
7.2% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 16 of the last 52 weeks; the most was 100% of its area, in 4 weeks, most recently on the May 5, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 7.2% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
29 flood losses since 2016, $1.2 million paid. The worst year was 2025, with 25. Foundations of the buildings, where recorded: 8% basements, 16% slabs, 52% crawl spaces, 24% elevated. Median water depth outside the building: 25 in.
| Year | Flood losses |
|---|---|
| 2016 | 1 |
| 2017 | 0 |
| 2018 | 0 |
| 2019 | 0 |
| 2020 | 2 |
| 2021 | 0 |
| 2022 | 1 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 25 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 47.86 in |
| 12 months to August 2026 | 44.24 in (-3.62) |
| 2025 | 55.24 in (+7.38) |
| Wettest year since 1895 | 1979: 66.73 in |
| Driest year since 1895 | 1930: 28.61 in |
| Days with 1 inch or more, normal at CALHOUN LOCK 2 (0 mi away) | 11.4 |
Homes
| Housing units | 4,173 |
| Median year built | 1976 |
| Built before 1980 | 57% |
| Built 2000 or later | 15% |
| Owner-occupied | 83% |
| Median value, owner-occupied | $148,500 |
| Single-family detached | 75% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Daviess County, KY | 17 mi | 7% | 64% |
| Hopkins County, KY | 21 mi | 11% | 64% |
| Muhlenberg County, KY | 23 mi | 2% | 46% |
| Webster County, KY | 23 mi | 10% | 69% |
| Ohio County, KY | 24 mi | 2% | 42% |
| Henderson County, KY | 25 mi | 5% | 63% |
| Hancock County, KY | 34 mi | 1% | 36% |
| Spencer County, IN | 36 mi | 3% | 66% |
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