Anderson County, Kansas
Shrink-swell clay limits houses without basements on 80% of Anderson County's mapped land, a higher share than 99% of US counties and the 4th highest of 105 Kansas counties. A shallow water table limits basements on 72%.
None of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list no flood losses here since 2016. 66% of homes were built before 1980, against 50% nationally; the median home dates from 1964.
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 Anderson County
| Expansive clay (limits slab homes) | 80.1% |
| High water table (limits basements) | 72.3% |
| Septic fields very limited | 98.3% |
| Clay swell (LEP, by area) | 7.5% |
| High-swell land (LEP 6%+) | 79.5% |
| Mapped soil | 373,708 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Woodson | 23% | n/a |
| Kenoma | 15% | over 99% |
| Eram | 10% | n/a |
| Wagstaff | 7% | n/a |
| Summit | 7% | n/a |
| Verdigris | 6% | n/a |
How we count · survey areas KS003 (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 80% of the mapped land.
On 72% of Anderson 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: 40.49 in, 0.05 in above the 1991-2020 average year of 40.44 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 16 of the last 52 weeks; the most was 72.6% of its area, on the September 8, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 68.6% |
| D1 moderate drought or worse | 0% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
FEMA's flood data list no flood losses in Anderson County since 2016.
Rain
| Average year, 1991-2020 | 40.44 in |
| 12 months to August 2026 | 40.49 in (+0.05) |
| 2025 | 37.61 in (-2.83) |
| Wettest year since 1895 | 1973: 60.93 in |
| Driest year since 1895 | 1936: 21.09 in |
| Days with 1 inch or more, normal at GARNETT 1 E (6 mi away) | 11.3 |
Homes
| Housing units | 3,586 |
| Median year built | 1964 |
| Built before 1980 | 66% |
| Built 2000 or later | 10% |
| Owner-occupied | 79% |
| Median value, owner-occupied | $171,400 |
| Single-family detached | 87% |
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 |
|---|---|---|---|
| Allen County, KS | 23 mi | 75% | 61% |
| Franklin County, KS | 24 mi | 75% | 70% |
| Coffey County, KS | 24 mi | 77% | 76% |
| Linn County, KS | 24 mi | 78% | 61% |
| Woodson County, KS | 34 mi | 73% | 72% |
| Bourbon County, KS | 35 mi | 69% | 58% |
| Miami County, KS | 35 mi | 83% | 67% |
| Osage County, KS | 38 mi | 77% | 69% |
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