San Juan County, Utah
USDA's soil survey flags shrink-swell clay on 3% of San Juan County's mapped land and a shallow water table under basements on 1%, both below the national shares of 15% and 29%. 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. 42% 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 San Juan County
| Expansive clay (limits slab homes) | 3.4% |
| High water table (limits basements) | 0.6% |
| Septic fields very limited | 47.7% |
| Clay swell (LEP, by area) | 2.4% |
| High-swell land (LEP 6%+) | 2.7% |
| Mapped soil | 4,760,983 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Rizno | 7% | n/a |
| Moenkopie | 3% | n/a |
| Sheppard | 3% | n/a |
| Skos | 2% | n/a |
| Begay | 2% | n/a |
| Aneth | 2% | n/a |
How we count · survey areas UT633 (2025-09-05), UT638 (2025-08-27), UT639 (2025-08-27), UT643 (2025-08-27), UT688 (2025-08-28), UT689 (2025-08-28)
What the numbers mean here
Rain over the 12 months to August 2026: 9.07 in, 1.12 in below the 1991-2020 average year of 10.19 in.
With shrink-swell clay on 3% and a shallow water table on 1% of the land, the soil survey points to neither problem across most of San Juan County; conditions still vary lot by lot.
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 32 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 | 95.1% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
FEMA's flood data list no flood losses in San Juan County since 2016.
Rain
| Average year, 1991-2020 | 10.19 in |
| 12 months to August 2026 | 9.07 in (-1.12) |
| 2025 | 8.19 in (-2.00) |
| Wettest year since 1895 | 1941: 19.04 in |
| Driest year since 1895 | 1950: 5.06 in |
| Days with 1 inch or more, normal at NATURAL BRIDGES NM (10 mi away) | 0.6 |
Homes
| Housing units | 5,679 |
| Median year built | 1986 |
| Built before 1980 | 42% |
| Built 2000 or later | 26% |
| Owner-occupied | 81% |
| Median value, owner-occupied | $224,200 |
| Single-family detached | 76% |
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 |
|---|---|---|---|
| Montezuma County, CO | 68 mi | 13% | 2% |
| Dolores County, CO | 71 mi | 12% | 2% |
| Wayne County, UT | 80 mi | 6% | 1% |
| San Miguel County, CO | 80 mi | 3% | 1% |
| Garfield County, UT | 92 mi | 4% | 1% |
| Grand County, UT | 96 mi | 4% | under 1% |
| Montrose County, CO | 100 mi | 22% | 5% |
| San Juan County, NM | 108 mi | 5% | 2% |
Sources: USDA SSURGO (September 5, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status