Gilpin County, Colorado
USDA's soil survey flags shrink-swell clay on 0% of Gilpin County's mapped land and a shallow water table under basements on 3%, 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. 45% of homes were built before 1980, against 50% nationally; the median home dates from 1984.
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 Gilpin County
| Expansive clay (limits slab homes) | 0.0% |
| High water table (limits basements) | 3.3% |
| Septic fields very limited | 90.6% |
| Clay swell (LEP, by area) | 1.4% |
| High-swell land (LEP 6%+) | 0.0% |
| Mapped soil | 96,000 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Legault | 12% | n/a |
| Catamount family | 7% | n/a |
| Resort | 4% | n/a |
| Cathedral | 4% | n/a |
| Ohman | 3% | n/a |
| Tahana | 1% | n/a |
How we count · survey areas CO645 (2025-08-29), CO653 (2025-08-29)
What the numbers mean here
Rain over the 12 months to August 2026: 16.72 in, 6.70 in below the 1991-2020 average year of 23.42 in.
USDA rates 91% of the land very limited for septic absorption fields.
With shrink-swell clay on 0% and a shallow water table on 3% of the land, the soil survey points to neither problem across most of Gilpin 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 46 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 | 38.9% |
| D4 exceptional | 0% |
Flood losses since 2016
FEMA's flood data list no flood losses in Gilpin County since 2016.
Rain
| Average year, 1991-2020 | 23.42 in |
| 12 months to August 2026 | 16.72 in (-6.70) |
| 2025 | 19.79 in (-3.63) |
| Wettest year since 1895 | 1983: 33.33 in |
| Driest year since 1895 | 1939: 12.88 in |
| Days with 1 inch or more, normal at COAL CREEK CANYON (8 mi away) | 3 |
Homes
| Housing units | 3,746 |
| Median year built | 1984 |
| Built before 1980 | 45% |
| Built 2000 or later | 18% |
| Owner-occupied | 88% |
| Median value, owner-occupied | $573,900 |
| Single-family detached | 92% |
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 |
|---|---|---|---|
| Clear Creek County, CO | 14 mi | 0% | 3% |
| Boulder County, CO | 18 mi | 9% | 6% |
| Jefferson County, CO | 25 mi | 17% | 2% |
| Broomfield County, CO | 26 mi | 46% | 1% |
| Denver County, CO | 35 mi | 15% | 3% |
| Grand County, CO | 35 mi | 5% | 6% |
| Summit County, CO | 36 mi | 4% | 5% |
| Douglas County, CO | 49 mi | 3% | 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