Teton County, Wyoming
USDA's soil survey flags shrink-swell clay on 7% of Teton County's mapped land and a shallow water table under basements on 6%, both below the national shares of 15% and 29%. 1.4% of the county is in drought on the October 13, 2026 Drought Monitor map, down from 10.7% a week earlier.
FEMA's flood data list 5 flood losses here since 2016. 32% of homes were built before 1980, against 50% nationally; the median home dates from 1989.
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 Teton County
| Expansive clay (limits slab homes) | 6.7% |
| High water table (limits basements) | 5.5% |
| Septic fields very limited | 74.2% |
| Clay swell (LEP, by area) | 2.9% |
| High-swell land (LEP 6%+) | 7.6% |
| Mapped soil | 2,584,899 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Koffgo | 3% | n/a |
| Tineman | 2% | n/a |
| Taglake | 2% | n/a |
| Yodal | 1% | n/a |
| Tetonville | 1% | n/a |
| Gany | 1% | n/a |
How we count · survey areas ID650 (2025-08-27), ID758 (2025-08-27), WY661 (2025-09-04), WY665 (2025-09-04), WY666 (2025-09-04), WY667 (2025-09-04)
What the numbers mean here
Rain over the 12 months to August 2026: 34.74 in, 0.89 in below the 1991-2020 average year of 35.63 in.
USDA rates 74% of the land very limited for septic absorption fields.
With shrink-swell clay on 7% and a shallow water table on 6% of the land, the soil survey points to neither problem across most of Teton County; conditions still vary lot by lot.
Drought
1.4% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 52 of the last 52 weeks; the most was 100% of its area, in 23 weeks, most recently on the September 15, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 1.4% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
5 flood losses since 2016, $84,492 paid. The worst year was 2017, with 4.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 4 |
| 2018 | 0 |
| 2019 | 1 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 35.63 in |
| 12 months to August 2026 | 34.74 in (-0.89) |
| 2025 | 36.33 in (+0.70) |
| Wettest year since 1895 | 1996: 50.38 in |
| Driest year since 1895 | 1919: 24.16 in |
| Days with 1 inch or more, normal at SNAKE RVR (13 mi away) | 2 |
Homes
| Housing units | 13,658 |
| Median year built | 1989 |
| Built before 1980 | 32% |
| Built 2000 or later | 26% |
| Owner-occupied | 58% |
| Median value, owner-occupied | $1.6 million |
| Single-family detached | 63% |
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 |
|---|---|---|---|
| Teton County, ID | 44 mi | 5% | 12% |
| Park County, WY | 51 mi | 12% | 9% |
| Fremont County, ID | 54 mi | 1% | 6% |
| Madison County, ID | 64 mi | under 1% | 14% |
| Bonneville County, ID | 75 mi | 11% | 4% |
| Sublette County, WY | 92 mi | 8% | 13% |
| Jefferson County, ID | 96 mi | 21% | 8% |
| Clark County, ID | 97 mi | 4% | 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