Trigg County, Kentucky
USDA's soil survey flags shrink-swell clay on under 1% of Trigg County's mapped land and a shallow water table under basements on 13%, both below the national shares of 15% and 29%. 10% 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. 42% of homes were built before 1980, against 50% nationally; the median home dates from 1985.
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 Trigg County
| Expansive clay (limits slab homes) | under 0.1% |
| High water table (limits basements) | 12.8% |
| Septic fields very limited | 54.0% |
| Clay swell (LEP, by area) | 3.3% |
| High-swell land (LEP 6%+) | 0.2% |
| Mapped soil | 307,994 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Hammack | 16% | n/a |
| Brandon | 14% | n/a |
| Baxter | 12% | n/a |
| Crider | 7% | 3% |
| Nicholson | 6% | n/a |
| Nolin | 6% | n/a |
How we count · survey areas KY629 (2025-09-08)
What the numbers mean here
Rain over the 12 months to August 2026: 38.12 in, 14.30 in below the 1991-2020 average year of 52.42 in.
USDA rates 54% of the land very limited for septic absorption fields.
With shrink-swell clay on under 1% and a shallow water table on 13% of the land, the soil survey points to neither problem across most of Trigg County; conditions still vary lot by lot.
Drought
10% of the county is in drought (D1 or worse) on the October 13, 2026 map. Part of the county was in drought in 29 of the last 52 weeks; the most was 100% of its area, in 10 weeks, most recently on the June 2, 2026 map.
| Category, October 13, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 99.1% |
| D1 moderate drought or worse | 10% |
| 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 Trigg County since 2016.
Rain
| Average year, 1991-2020 | 52.42 in |
| 12 months to August 2026 | 38.12 in (-14.30) |
| 2025 | 54.80 in (+2.38) |
| Wettest year since 1895 | 2011: 71.73 in |
| Driest year since 1895 | 1963: 31.11 in |
| Days with 1 inch or more, normal at CADIZ (4 mi away) | 15.8 |
Homes
| Housing units | 7,652 |
| Median year built | 1985 |
| Built before 1980 | 42% |
| Built 2000 or later | 25% |
| Owner-occupied | 77% |
| Median value, owner-occupied | $207,700 |
| 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 |
|---|---|---|---|
| Lyon County, KY | 20 mi | 0% | 18% |
| Christian County, KY | 21 mi | under 1% | 34% |
| Caldwell County, KY | 24 mi | 6% | 43% |
| Stewart County, TN | 25 mi | under 1% | 27% |
| Calloway County, KY | 26 mi | under 1% | 54% |
| Marshall County, KY | 27 mi | 1% | 57% |
| Montgomery County, TN | 34 mi | 1% | 25% |
| Houston County, TN | 37 mi | 0% | 13% |
Sources: USDA SSURGO (September 8, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status