Salt Lake County, Utah
A shallow water table limits basements on 17% of Salt Lake County's mapped land and the 5th highest of 28 Utah counties. Shrink-swell clay limits houses without basements on 13%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 56 flood losses here since 2016, 76% of them in buildings with basements. 43% of homes were built before 1980, against 50% nationally; the median home dates from 1986.
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 Salt Lake County
| Expansive clay (limits slab homes) | 12.6% |
| High water table (limits basements) | 16.7% |
| Septic fields very limited | 68.5% |
| Clay swell (LEP, by area) | 3.7% |
| High-swell land (LEP 6%+) | 14.8% |
| Urban land, not rated | 2.7% |
| Mapped soil | 517,168 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Bingham | 4% | n/a |
| Harkers | 4% | n/a |
| Lasil | 3% | n/a |
| Lucky Star | 2% | n/a |
| Dromedary | 2% | n/a |
| Agassiz | 2% | n/a |
How we count · survey areas UT611 (2025-08-26), UT612 (2025-08-26), UT613 (2025-08-27)
What the numbers mean here
On 17% of Salt Lake 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: 18.29 in, 3.97 in below the 1991-2020 average year of 22.26 in.
USDA rates 69% 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 52 of the last 52 weeks; the most was 100% of its area, in 29 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 | 100% |
| D3 extreme or worse | 0.4% |
| D4 exceptional | 0% |
Flood losses since 2016
56 flood losses since 2016, $177,218 paid. The worst year was 2023, with 18. Foundations of the buildings, where recorded: 76% basements, 19% slabs, 5% elevated.
| Year | Flood losses |
|---|---|
| 2016 | 1 |
| 2017 | 8 |
| 2018 | 1 |
| 2019 | 3 |
| 2020 | 3 |
| 2021 | 6 |
| 2022 | 3 |
| 2023 | 18 |
| 2024 | 6 |
| 2025 | 4 |
| 2026 to date | 3 |
Rain
| Average year, 1991-2020 | 22.26 in |
| 12 months to August 2026 | 18.29 in (-3.97) |
| 2025 | 18.05 in (-4.21) |
| Wettest year since 1895 | 1983: 36.93 in |
| Driest year since 1895 | 2020: 13.26 in |
| Days with 1 inch or more, normal at COTTONWOOD WEIR (8 mi away) | 3.3 |
Homes
| Housing units | 449,662 |
| Median year built | 1986 |
| Built before 1980 | 43% |
| Built 2000 or later | 32% |
| Owner-occupied | 66% |
| Median value, owner-occupied | $525,700 |
| Single-family detached | 60% |
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 |
|---|---|---|---|
| Davis County, UT | 30 mi | 4% | 16% |
| Morgan County, UT | 34 mi | 15% | 2% |
| Utah County, UT | 40 mi | 7% | 10% |
| Weber County, UT | 42 mi | 7% | 20% |
| Wasatch County, UT | 46 mi | 11% | 5% |
| Summit County, UT | 52 mi | 9% | 6% |
| Tooele County, UT | 65 mi | 0% | 36% |
| Cache County, UT | 74 mi | 22% | 18% |
Sources: USDA SSURGO (August 27, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status