Sheridan County, Wyoming
Shrink-swell clay limits houses without basements on 21% of Sheridan County's mapped land, a higher share than 71% of US counties and the 4th highest of 22 Wyoming counties. A shallow water table limits basements on 1%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 16 flood losses here since 2016. 46% of homes were built before 1980, against 50% nationally; the median home dates from 1983.
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 Sheridan County
| Expansive clay (limits slab homes) | 20.9% |
| High water table (limits basements) | 1.4% |
| Septic fields very limited | 70.5% |
| Clay swell (LEP, by area) | 4.4% |
| High-swell land (LEP 6%+) | 21.6% |
| Mapped soil | 1,622,175 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Shingle | 10% | n/a |
| Cloud Peak | 6% | n/a |
| Theedle | 5% | n/a |
| Kishona | 4% | n/a |
| Agneston | 3% | n/a |
| Samday | 3% | n/a |
How we count · survey areas WY633 (2025-09-04), WY650 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 4.4% by land area here, and 22% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 21% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 21% of Sheridan County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 15.46 in, 2.98 in below the 1991-2020 average year of 18.44 in.
USDA rates 71% 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 43 of the last 52 weeks; the most was 100% of its area, in 28 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 | 92.9% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
16 flood losses since 2016, $131,141 paid. The worst year was 2019, with 11.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 0 |
| 2018 | 4 |
| 2019 | 11 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 1 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 18.44 in |
| 12 months to August 2026 | 15.46 in (-2.98) |
| 2025 | 21.04 in (+2.60) |
| Wettest year since 1895 | 1927: 28.96 in |
| Driest year since 1895 | 1902: 10.86 in |
| Days with 1 inch or more, normal at SHERIDAN CO AP (4 mi away) | 1.2 |
Homes
| Housing units | 15,461 |
| Median year built | 1983 |
| Built before 1980 | 46% |
| Built 2000 or later | 31% |
| Owner-occupied | 71% |
| Median value, owner-occupied | $394,900 |
| Single-family detached | 74% |
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, WY | 53 mi | 18% | 1% |
| Big Horn County, MT | 53 mi | 30% | 1% |
| Big Horn County, WY | 58 mi | 12% | 4% |
| Washakie County, WY | 74 mi | 5% | 2% |
| Powder River County, MT | 78 mi | 30% | under 1% |
| Campbell County, WY | 78 mi | 22% | 1% |
| Rosebud County, MT | 97 mi | 25% | under 1% |
| Treasure County, MT | 102 mi | 44% | 4% |
Sources: USDA SSURGO (September 4, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status