Callaway County, Missouri
A shallow water table limits basements on 63% of Callaway County's mapped land, a higher share than 76% of US counties. Shrink-swell clay limits houses without basements on 54%.
2.4% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 28 flood losses here since 2016. 42% 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 Callaway County
| Expansive clay (limits slab homes) | 54.0% |
| High water table (limits basements) | 63.2% |
| Septic fields very limited | 98.1% |
| Clay swell (LEP, by area) | 7.4% |
| High-swell land (LEP 6%+) | 68.2% |
| Mapped soil | 542,355 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Keswick | 17% | n/a |
| Mexico | 12% | n/a |
| Goss | 12% | 0% |
| Lindley | 9% | n/a |
| Winfield | 6% | n/a |
| Gorin | 5% | n/a |
How we count · survey areas MO027 (2025-09-02)
What the numbers mean here
Clay swell averages a linear extensibility of 7.4% by land area here, and 68% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 54% of the mapped land.
Clay shrinks as it dries: 2.4% of the county is in drought on the latest map, and 54% of Callaway County's mapped land has shrink-swell clay.
On 63% of Callaway 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: 42.67 in, 0.22 in above the 1991-2020 average year of 42.45 in.
USDA rates 98% of the land very limited for septic absorption fields.
Drought
2.4% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 19 of the last 52 weeks; the most was 100% of its area, in 6 weeks, most recently on the February 10, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 2.4% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
28 flood losses since 2016, $1.0 million paid. The worst year was 2019, with 18.
| Year | Flood losses |
|---|---|
| 2016 | 6 |
| 2017 | 1 |
| 2018 | 0 |
| 2019 | 18 |
| 2020 | 1 |
| 2021 | 2 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 42.45 in |
| 12 months to August 2026 | 42.67 in (+0.22) |
| 2025 | 34.31 in (-8.14) |
| Wettest year since 1895 | 1993: 63.05 in |
| Driest year since 1895 | 1901: 22.74 in |
| Days with 1 inch or more, normal at FULTON (1 mi away) | 11.6 |
Homes
| Housing units | 18,645 |
| Median year built | 1987 |
| Built before 1980 | 42% |
| Built 2000 or later | 30% |
| Owner-occupied | 76% |
| Median value, owner-occupied | $201,600 |
| Single-family detached | 73% |
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 |
|---|---|---|---|
| Boone County, MO | 23 mi | 71% | 78% |
| Montgomery County, MO | 26 mi | 67% | 76% |
| Osage County, MO | 26 mi | 29% | 70% |
| Audrain County, MO | 27 mi | 90% | 98% |
| Cole County, MO | 30 mi | 14% | 69% |
| Gasconade County, MO | 35 mi | 37% | 76% |
| Moniteau County, MO | 38 mi | 23% | 80% |
| Warren County, MO | 41 mi | 52% | 59% |
Sources: USDA SSURGO (September 2, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status