Dolores County, Colorado
USDA's soil survey flags shrink-swell clay on 12% of Dolores County's mapped land and a shallow water table under basements on 2%, both below the national shares of 15% and 29%. The soil survey maps 79% of the county's land area; these shares describe the mapped part.
96% 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. 50% of homes were built before 1980, against 50% nationally; the median home dates from 1980.
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 Dolores County
| Expansive clay (limits slab homes) | 12.4% |
| High water table (limits basements) | 1.7% |
| Septic fields very limited | 80.8% |
| Clay swell (LEP, by area) | 3.6% |
| High-swell land (LEP 6%+) | 13.8% |
| Mapped soil | 542,600 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Wetherill | 9% | n/a |
| Frisco | 4% | n/a |
| Granath | 4% | n/a |
| Pulpit | 3% | n/a |
| Sharps | 3% | n/a |
| Fughes | 3% | n/a |
How we count · survey areas CO671 (2025-08-29), CO672 (2025-08-29)
What the numbers mean here
Rain over the 12 months to August 2026: 19.49 in, 1.94 in below the 1991-2020 average year of 21.43 in.
USDA rates 81% of the land very limited for septic absorption fields.
With shrink-swell clay on 12% and a shallow water table on 2% of the land, the soil survey points to neither problem across most of Dolores County; conditions still vary lot by lot.
Drought
96% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 39 of the last 52 weeks; the most was 100% of its area, in 29 weeks, most recently on the September 22, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 96% |
| D2 severe or worse | 64.7% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
FEMA's flood data list no flood losses in Dolores County since 2016.
Rain
| Average year, 1991-2020 | 21.43 in |
| 12 months to August 2026 | 19.49 in (-1.94) |
| 2025 | 18.12 in (-3.31) |
| Wettest year since 1895 | 1941: 40.53 in |
| Driest year since 1895 | 2020: 12.45 in |
| Days with 1 inch or more, normal at CORTEZ (27 mi away) | 0.7 |
Homes
| Housing units | 1,572 |
| Median year built | 1980 |
| Built before 1980 | 50% |
| Built 2000 or later | 25% |
| Owner-occupied | 81% |
| Median value, owner-occupied | $247,600 |
| 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 |
|---|---|---|---|
| San Miguel County, CO | 20 mi | 3% | 1% |
| Montezuma County, CO | 28 mi | 13% | 2% |
| San Juan County, CO | 46 mi | 0% | 1% |
| La Plata County, CO | 48 mi | 10% | 3% |
| Montrose County, CO | 48 mi | 22% | 5% |
| Ouray County, CO | 49 mi | 19% | 6% |
| Hinsdale County, CO | 63 mi | under 1% | 2% |
| San Juan County, UT | 71 mi | 3% | 1% |
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