Clearwater County, Idaho
USDA's soil survey flags shrink-swell clay on 1% of Clearwater County's mapped land and a shallow water table under basements on 14%, both below the national shares of 15% and 29%. The soil survey maps 59% of the county's land area; these shares describe the mapped part.
51% 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. 57% of homes were built before 1980, against 50% nationally; the median home dates from 1977.
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 Clearwater County
| Expansive clay (limits slab homes) | 1.3% |
| High water table (limits basements) | 14.3% |
| Septic fields very limited | 92.9% |
| Clay swell (LEP, by area) | 2.7% |
| High-swell land (LEP 6%+) | 1.9% |
| Mapped soil | 920,689 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Brodeer | 8% | n/a |
| Dullaxe | 7% | n/a |
| Grangemont | 5% | n/a |
| Mushel | 4% | n/a |
| Kauder | 4% | n/a |
| Grandad | 4% | n/a |
How we count · survey areas ID612 (2025-08-27), ID670 (2025-08-27)
What the numbers mean here
Rain over the 12 months to August 2026: 45.01 in, 0.57 in below the 1991-2020 average year of 45.58 in.
USDA rates 93% of the land very limited for septic absorption fields.
With shrink-swell clay on 1% and a shallow water table on 14% of the land, the soil survey points to neither problem across most of Clearwater County; conditions still vary lot by lot.
Drought
51% 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 9 weeks, most recently on the December 16, 2025 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 87.6% |
| D1 moderate drought or worse | 51% |
| D2 severe or worse | 24.5% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
FEMA's flood data list no flood losses in Clearwater County since 2016.
Rain
| Average year, 1991-2020 | 45.58 in |
| 12 months to August 2026 | 45.01 in (-0.57) |
| 2025 | 41.83 in (-3.75) |
| Wettest year since 1895 | 1927: 67.39 in |
| Driest year since 1895 | 1987: 30.25 in |
| Days with 1 inch or more, normal at HEADQUARTERS (8 mi away) | 5.2 |
Homes
| Housing units | 4,626 |
| Median year built | 1977 |
| Built before 1980 | 57% |
| Built 2000 or later | 17% |
| Owner-occupied | 83% |
| Median value, owner-occupied | $268,200 |
| Single-family detached | 73% |
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 |
|---|---|---|---|
| Mineral County, MT | 41 mi | under 1% | 4% |
| Lewis County, ID | 47 mi | 23% | 33% |
| Shoshone County, ID | 48 mi | under 1% | 4% |
| Latah County, ID | 52 mi | 5% | 43% |
| Idaho County, ID | 58 mi | 9% | 12% |
| Nez Perce County, ID | 58 mi | 7% | 15% |
| Benewah County, ID | 60 mi | 1% | 40% |
| Sanders County, MT | 78 mi | 2% | 3% |
Sources: USDA SSURGO (August 27, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status