Grant County, Oklahoma
Shrink-swell clay limits houses without basements on 48% of Grant County's mapped land, a higher share than 90% of US counties and the 9th highest of 77 Oklahoma counties. A shallow water table limits basements on 10%.
100% 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. 73% of homes were built before 1980, against 50% nationally; the median home dates from 1967.
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 Grant County
| Expansive clay (limits slab homes) | 47.8% |
| High water table (limits basements) | 9.7% |
| Septic fields very limited | 71.8% |
| Clay swell (LEP, by area) | 5.4% |
| High-swell land (LEP 6%+) | 45.8% |
| Mapped soil | 642,739 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Kirkland | 22% | n/a |
| Pond Creek | 7% | n/a |
| Tabler | 6% | n/a |
| Bethany | 6% | n/a |
| Renfrow | 5% | n/a |
| McLain | 5% | n/a |
How we count · survey areas OK053 (2025-08-29)
What the numbers mean here
Clay swell averages a linear extensibility of 5.4% 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 48% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 48% of Grant County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 28.85 in, 4.18 in below the 1991-2020 average year of 33.03 in.
USDA rates 72% of the land very limited for septic absorption fields.
Drought
100% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 33 of the last 52 weeks; the most was 100% of its area, in 24 weeks, most recently on the October 13, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 100% |
| D2 severe or worse | 96.4% |
| D3 extreme or worse | 0.1% |
| D4 exceptional | 0% |
Flood losses since 2016
FEMA's flood data list no flood losses in Grant County since 2016.
Rain
| Average year, 1991-2020 | 33.03 in |
| 12 months to August 2026 | 28.85 in (-4.18) |
| 2025 | 38.13 in (+5.10) |
| Wettest year since 1895 | 1957: 45.62 in |
| Driest year since 1895 | 1910: 13.78 in |
| Days with 1 inch or more, normal at LAMONT (15 mi away) | 10.6 |
Homes
| Housing units | 2,163 |
| Median year built | 1967 |
| Built before 1980 | 73% |
| Built 2000 or later | 14% |
| Owner-occupied | 76% |
| Median value, owner-occupied | $105,700 |
| Single-family detached | 88% |
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 |
|---|---|---|---|
| Garfield County, OK | 28 mi | 46% | 6% |
| Alfalfa County, OK | 30 mi | 8% | 10% |
| Harper County, KS | 32 mi | 10% | 12% |
| Sumner County, KS | 35 mi | 47% | 8% |
| Kay County, OK | 36 mi | 59% | 19% |
| Noble County, OK | 41 mi | 38% | 1% |
| Major County, OK | 53 mi | 13% | 7% |
| Kingman County, KS | 56 mi | 8% | 11% |
Sources: USDA SSURGO (August 29, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status