DeKalb County, Tennessee
A shallow water table limits basements on 19% of DeKalb County's mapped land. Shrink-swell clay limits houses without basements on 13%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 12 flood losses here since 2016. 42% of homes were built before 1980, against 50% nationally; the median home dates from 1986.
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 DeKalb County
| Expansive clay (limits slab homes) | 13.3% |
| High water table (limits basements) | 19.3% |
| Septic fields very limited | 72.9% |
| Clay swell (LEP, by area) | 3.8% |
| High-swell land (LEP 6%+) | 14.7% |
| Mapped soil | 210,800 acres |
| Soil series | Share here | Series nationally: high water table |
|---|---|---|
| Mimosa | 16% | n/a |
| Hawthorne | 15% | n/a |
| Dickson | 8% | n/a |
| Dellrose | 7% | n/a |
| Christian | 7% | n/a |
| Fullerton | 4% | 0% |
How we count · survey areas TN041 (2025-08-28)
What the numbers mean here
On 19% of DeKalb County's mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.
Rain over the 12 months to August 2026: 46.00 in, 10.05 in below the 1991-2020 average year of 56.05 in.
USDA rates 73% of the land very limited for septic absorption fields.
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 22 of the last 52 weeks; the most was 100% of its area, in 11 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 | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
12 flood losses since 2016, $123,134 paid. The worst year was 2021, with 4.
| Year | Flood losses |
|---|---|
| 2016 | 1 |
| 2017 | 4 |
| 2018 | 0 |
| 2019 | 2 |
| 2020 | 1 |
| 2021 | 4 |
| 2022 | 0 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 56.05 in |
| 12 months to August 2026 | 46.00 in (-10.05) |
| 2025 | 54.96 in (-1.09) |
| Wettest year since 1895 | 1973: 72.99 in |
| Driest year since 1895 | 2007: 34.77 in |
| Days with 1 inch or more, normal at SMITHVILLE 2 SE (4 mi away) | 16.2 |
Homes
| Housing units | 10,155 |
| Median year built | 1986 |
| Built before 1980 | 42% |
| Built 2000 or later | 30% |
| Owner-occupied | 73% |
| Median value, owner-occupied | $235,500 |
| Single-family detached | 78% |
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 |
|---|---|---|---|
| Cannon County, TN | 18 mi | 17% | 28% |
| Smith County, TN | 21 mi | 41% | 3% |
| Warren County, TN | 21 mi | under 1% | 26% |
| White County, TN | 21 mi | 2% | 8% |
| Putnam County, TN | 22 mi | 6% | 12% |
| Jackson County, TN | 27 mi | 23% | 6% |
| Wilson County, TN | 28 mi | 16% | 14% |
| Van Buren County, TN | 29 mi | 1% | 2% |
Sources: USDA SSURGO (August 28, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status