Coffey County, Kansas
Shrink-swell clay limits houses without basements on 77% of Coffey County's mapped land, a higher share than 98% of US counties. A shallow water table limits basements on 76%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 2 flood losses here since 2016. 62% of homes were built before 1980, against 50% nationally; the median home dates from 1970.
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 Coffey County
| Expansive clay (limits slab homes) | 77.2% |
| High water table (limits basements) | 76.1% |
| Septic fields very limited | 95.8% |
| Clay swell (LEP, by area) | 7.5% |
| High-swell land (LEP 6%+) | 78.5% |
| Mapped soil | 418,605 acres |
How we count · survey areas KS031 (2025-08-26)
What the numbers mean here
Clay swell averages a linear extensibility of 7.5% by land area here, and 79% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 77% of the mapped land.
On 76% of Coffey 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: 39.45 in, 0.67 in above the 1991-2020 average year of 38.78 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. Part of the county was in drought in 2 of the last 52 weeks; the most was 69.4% of its area, on the September 8, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 85.7% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
2 flood losses since 2016, $134,622 paid. The worst year was 2019, with 2.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 0 |
| 2018 | 0 |
| 2019 | 2 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 38.78 in |
| 12 months to August 2026 | 39.45 in (+0.67) |
| 2025 | 38.54 in (-0.24) |
| Wettest year since 1895 | 1951: 57.09 in |
| Driest year since 1895 | 1936: 20.17 in |
| Days with 1 inch or more, normal at JOHN REDMOND LAKE (2 mi away) | 11 |
Homes
| Housing units | 3,998 |
| Median year built | 1970 |
| Built before 1980 | 62% |
| Built 2000 or later | 18% |
| Owner-occupied | 76% |
| Median value, owner-occupied | $157,400 |
| Single-family detached | 84% |
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 |
|---|---|---|---|
| Anderson County, KS | 24 mi | 80% | 72% |
| Woodson County, KS | 24 mi | 73% | 72% |
| Lyon County, KS | 28 mi | 80% | 53% |
| Osage County, KS | 29 mi | 77% | 69% |
| Franklin County, KS | 33 mi | 75% | 70% |
| Allen County, KS | 34 mi | 75% | 61% |
| Greenwood County, KS | 37 mi | 78% | 39% |
| Wilson County, KS | 47 mi | 69% | 60% |
Sources: USDA SSURGO (August 26, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status