Dearborn County, Indiana
Shrink-swell clay limits houses without basements on 38% of Dearborn County's mapped land, a higher share than 86% of US counties. A shallow water table limits basements on 36%.
None 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, 24% of them in buildings with basements. 47% of homes were built before 1980, against 50% nationally; the median home dates from 1982.
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 Dearborn County
| Expansive clay (limits slab homes) | 38.0% |
| High water table (limits basements) | 35.9% |
| Septic fields very limited | 98.0% |
| Clay swell (LEP, by area) | 5.3% |
| High-swell land (LEP 6%+) | 45.6% |
| Mapped soil | 196,890 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Eden | 30% | 6% |
| Carmel | 13% | n/a |
| Switzerland | 9% | n/a |
| Weisburg | 8% | n/a |
| Bonnell | 7% | n/a |
| Cincinnati | 5% | n/a |
How we count · survey areas IN029 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 5.3% by land area here, and 46% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 38% of the mapped land.
On 36% of Dearborn 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: 50.18 in, 4.53 in above the 1991-2020 average year of 45.65 in.
USDA rates 98% 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 | 25.7% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
29 flood losses since 2016, $726,329 paid. The worst year was 2018, with 11. Foundations of the buildings, where recorded: 24% basements, 33% slabs, 5% crawl spaces, 38% elevated.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 0 |
| 2018 | 11 |
| 2019 | 4 |
| 2020 | 0 |
| 2021 | 3 |
| 2022 | 0 |
| 2023 | 1 |
| 2024 | 1 |
| 2025 | 7 |
| 2026 to date | 2 |
Rain
| Average year, 1991-2020 | 45.65 in |
| 12 months to August 2026 | 50.18 in (+4.53) |
| 2025 | 48.72 in (+3.07) |
| Wettest year since 1895 | 2011: 64.59 in |
| Driest year since 1895 | 1934: 22.72 in |
| Days with 1 inch or more, normal at CINCINNATI NORTHERN KY AP (18 mi away) | 10.8 |
Homes
| Housing units | 21,098 |
| Median year built | 1982 |
| Built before 1980 | 47% |
| Built 2000 or later | 22% |
| Owner-occupied | 85% |
| Median value, owner-occupied | $243,400 |
| Single-family detached | 82% |
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 |
|---|---|---|---|
| Ohio County, IN | 14 mi | 40% | 28% |
| Ripley County, IN | 16 mi | 5% | 77% |
| Boone County, KY | 18 mi | 7% | 29% |
| Franklin County, IN | 19 mi | 15% | 53% |
| Switzerland County, IN | 22 mi | 41% | 40% |
| Hamilton County, OH | 23 mi | 7% | 9% |
| Gallatin County, KY | 27 mi | 11% | 10% |
| Kenton County, KY | 28 mi | 14% | 26% |
Sources: USDA SSURGO (September 4, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status