Garvin County, Oklahoma
Shrink-swell clay limits houses without basements on 30% of Garvin County's mapped land, a higher share than 80% of US counties. A shallow water table limits basements on 6%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 17 flood losses here since 2016. 65% of homes were built before 1980, against 50% nationally; the median home dates from 1973.
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 Garvin County
| Expansive clay (limits slab homes) | 30.3% |
| High water table (limits basements) | 6.2% |
| Septic fields very limited | 76.5% |
| Clay swell (LEP, by area) | 5.0% |
| High-swell land (LEP 6%+) | 34.4% |
| Mapped soil | 520,909 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Stephenville | 11% | 0% |
| Renfrow | 9% | n/a |
| Clarita | 8% | n/a |
| Zaneis | 7% | n/a |
| Teller | 5% | n/a |
| Port | 5% | n/a |
How we count · survey areas OK049 (2025-08-29)
What the numbers mean here
Clay swell averages a linear extensibility of 5.0% by land area here, and 34% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 30% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 30% of Garvin County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 26.45 in, 11.69 in below the 1991-2020 average year of 38.14 in.
USDA rates 77% 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 47 of the last 52 weeks; the most was 100% of its area, in 34 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 | 42.2% |
| D3 extreme or worse | 12% |
| D4 exceptional | 0% |
Flood losses since 2016
17 flood losses since 2016, $1.0 million paid. The worst year was 2016, with 6.
| Year | Flood losses |
|---|---|
| 2016 | 6 |
| 2017 | 3 |
| 2018 | 0 |
| 2019 | 3 |
| 2020 | 2 |
| 2021 | 2 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 1 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 38.14 in |
| 12 months to August 2026 | 26.45 in (-11.69) |
| 2025 | 42.17 in (+4.03) |
| Wettest year since 1895 | 2015: 61.71 in |
| Driest year since 1895 | 1963: 19.39 in |
| Days with 1 inch or more, normal at HENNEPIN 5 N (9 mi away) | 12 |
Homes
| Housing units | 12,081 |
| Median year built | 1973 |
| Built before 1980 | 65% |
| Built 2000 or later | 14% |
| Owner-occupied | 68% |
| Median value, owner-occupied | $147,800 |
| Single-family detached | 80% |
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 |
|---|---|---|---|
| Murray County, OK | 21 mi | 29% | 7% |
| McClain County, OK | 23 mi | 12% | 5% |
| Carter County, OK | 32 mi | 23% | 3% |
| Cleveland County, OK | 34 mi | 21% | 5% |
| Stephens County, OK | 35 mi | 19% | 2% |
| Pontotoc County, OK | 35 mi | 28% | 15% |
| Grady County, OK | 39 mi | 7% | 2% |
| Pottawatomie County, OK | 40 mi | 23% | 6% |
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