Montrose County, Colorado
Shrink-swell clay limits houses without basements on 22% of Montrose County's mapped land, a higher share than 73% of US counties and the 7th highest of 63 Colorado counties. A shallow water table limits basements on 5%.
The soil survey maps 41% of the county's land area; these shares describe the mapped part. 85.8% of the county is in drought on the October 13, 2026 Drought Monitor map, down from 100% a week earlier. FEMA's flood data list 2 flood losses here since 2016. 37% of homes were built before 1980, against 50% nationally; the median home dates from 1991.
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 Montrose County
| Expansive clay (limits slab homes) | 22.5% |
| High water table (limits basements) | 4.9% |
| Septic fields very limited | 76.7% |
| Clay swell (LEP, by area) | 4.5% |
| High-swell land (LEP 6%+) | 21.6% |
| Urban land, not rated | 1.2% |
| Mapped soil | 591,590 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Cerro | 7% | n/a |
| Mesa | 6% | n/a |
| Barboncito | 5% | n/a |
| Montrose | 4% | n/a |
| Persayo | 4% | n/a |
| Lazear | 4% | n/a |
How we count · survey areas CO677 (2025-08-29), CO679 (2025-08-29)
What the numbers mean here
Clay swell averages a linear extensibility of 4.5% 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 22% of the mapped land.
Clay shrinks as it dries: 85.8% of the county is in drought on the latest map, and 22% of Montrose County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 11.98 in, 2.90 in below the 1991-2020 average year of 14.88 in.
USDA rates 77% of the land very limited for septic absorption fields.
Drought
85.8% 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 31 weeks, most recently on the October 6, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 85.8% |
| D2 severe or worse | 15.9% |
| D3 extreme or worse | 2.1% |
| D4 exceptional | 0% |
Flood losses since 2016
2 flood losses since 2016, $35,999 paid. The worst year was 2021, with 1.
| Year | Flood losses |
|---|---|
| 2016 | 1 |
| 2017 | 0 |
| 2018 | 0 |
| 2019 | 0 |
| 2020 | 0 |
| 2021 | 1 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 14.88 in |
| 12 months to August 2026 | 11.98 in (-2.90) |
| 2025 | 11.09 in (-3.79) |
| Wettest year since 1895 | 1941: 26.69 in |
| Driest year since 1895 | 2020: 7.81 in |
| Days with 1 inch or more, normal at MONTROSE #2 (22 mi away) | 0 |
Homes
| Housing units | 19,758 |
| Median year built | 1991 |
| Built before 1980 | 37% |
| Built 2000 or later | 37% |
| Owner-occupied | 75% |
| Median value, owner-occupied | $388,400 |
| Single-family detached | 68% |
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 | 29 mi | 3% | 1% |
| Ouray County, CO | 31 mi | 19% | 6% |
| Delta County, CO | 38 mi | 12% | 3% |
| Mesa County, CO | 43 mi | 13% | 1% |
| Dolores County, CO | 48 mi | 12% | 2% |
| San Juan County, CO | 54 mi | 0% | 1% |
| Hinsdale County, CO | 62 mi | under 1% | 2% |
| Gunnison County, CO | 68 mi | 9% | 6% |
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