Miami County, Kansas
Shrink-swell clay limits houses without basements on 83% of Miami County's mapped land, a higher share than 100% of US counties and the highest of 105 Kansas counties. A shallow water table limits basements on 67%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 12 flood losses here since 2016. 43% of homes were built before 1980, against 50% nationally; the median home dates from 1987.
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 Miami County
| Expansive clay (limits slab homes) | 83.3% |
| High water table (limits basements) | 67.2% |
| Septic fields very limited | 97.7% |
| Clay swell (LEP, by area) | 7.3% |
| High-swell land (LEP 6%+) | 80.0% |
| Mapped soil | 377,895 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Summit | 14% | n/a |
| Wagstaff | 10% | n/a |
| Eram | 10% | n/a |
| Kenoma | 10% | over 99% |
| Bucyrus | 9% | n/a |
| Clareson | 7% | n/a |
How we count · survey areas KS121 (2025-08-26)
What the numbers mean here
Clay swell averages a linear extensibility of 7.3% by land area here, and 80% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 83% of the mapped land.
On 67% of Miami 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: 36.80 in, 3.53 in below the 1991-2020 average year of 40.33 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. Part of the county was in drought in 14 of the last 52 weeks; the most was 100% of its area, on the January 6, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 34.1% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
12 flood losses since 2016, $505,430 paid. The worst year was 2017, with 11.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 11 |
| 2018 | 1 |
| 2019 | 0 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 40.33 in |
| 12 months to August 2026 | 36.80 in (-3.53) |
| 2025 | 34.55 in (-5.78) |
| Wettest year since 1895 | 1973: 62.48 in |
| Driest year since 1895 | 1936: 22.41 in |
| Days with 1 inch or more, normal at OSAWATOMIE (8 mi away) | 12 |
Homes
| Housing units | 14,262 |
| Median year built | 1987 |
| Built before 1980 | 43% |
| Built 2000 or later | 31% |
| Owner-occupied | 78% |
| Median value, owner-occupied | $287,700 |
| 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 |
|---|---|---|---|
| Johnson County, KS | 22 mi | 73% | 65% |
| Franklin County, KS | 24 mi | 75% | 70% |
| Linn County, KS | 24 mi | 78% | 61% |
| Cass County, MO | 26 mi | 68% | 80% |
| Douglas County, KS | 34 mi | 56% | 51% |
| Bates County, MO | 34 mi | 70% | 75% |
| Anderson County, KS | 35 mi | 80% | 72% |
| Wyandotte County, KS | 38 mi | 61% | 28% |
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