Washington County, Colorado
USDA's soil survey flags shrink-swell clay on 11% of Washington County's mapped land and a shallow water table under basements on 1%, both below the national shares of 15% and 29%. 8.8% 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. 73% of homes were built before 1980, against 50% nationally; the median home dates from 1958.
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 Washington County
| Expansive clay (limits slab homes) | 11.3% |
| High water table (limits basements) | 1.1% |
| Septic fields very limited | 36.9% |
| Clay swell (LEP, by area) | 4.2% |
| High-swell land (LEP 6%+) | 34.8% |
| Mapped soil | 1,610,116 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Weld | 15% | n/a |
| Valent | 13% | n/a |
| Platner | 9% | n/a |
| Ascalon | 8% | n/a |
| Colby | 8% | n/a |
| Rago | 6% | n/a |
How we count · survey areas CO121 (2025-08-29)
What the numbers mean here
Rain over the 12 months to August 2026: 17.95 in, 1.75 in above the 1991-2020 average year of 16.20 in.
With shrink-swell clay on 11% and a shallow water table on 1% of the land, the soil survey points to neither problem across most of Washington County; conditions still vary lot by lot.
Drought
8.8% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 35 of the last 52 weeks; the most was 100% of its area, in 8 weeks, most recently on the May 19, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 26.2% |
| D1 moderate drought or worse | 8.8% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
FEMA's flood data list no flood losses in Washington County since 2016.
Rain
| Average year, 1991-2020 | 16.20 in |
| 12 months to August 2026 | 17.95 in (+1.75) |
| 2025 | 19.37 in (+3.17) |
| Wettest year since 1895 | 1915: 25.06 in |
| Driest year since 1895 | 2002: 9.46 in |
| Days with 1 inch or more, normal at AKRON 4 E (14 mi away) | 2.2 |
Homes
| Housing units | 2,287 |
| Median year built | 1958 |
| Built before 1980 | 73% |
| Built 2000 or later | 12% |
| Owner-occupied | 74% |
| Median value, owner-occupied | $226,200 |
| Single-family detached | 83% |
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 |
|---|---|---|---|
| Morgan County, CO | 38 mi | 10% | 3% |
| Yuma County, CO | 42 mi | 5% | 1% |
| Logan County, CO | 53 mi | 9% | 5% |
| Kit Carson County, CO | 56 mi | 9% | 3% |
| Adams County, CO | 60 mi | 11% | 2% |
| Phillips County, CO | 63 mi | 1% | under 1% |
| Arapahoe County, CO | 64 mi | 22% | 1% |
| Elbert County, CO | 66 mi | 11% | 2% |
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