Hamilton County, Texas
Shrink-swell clay limits houses without basements on 31% of Hamilton County's mapped land, a higher share than 81% of US counties. A shallow water table limits basements on under 1%.
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. 69% of homes were built before 1980, against 50% nationally; the median home dates from 1965.
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 Hamilton County
| Expansive clay (limits slab homes) | 30.5% |
| High water table (limits basements) | 0.1% |
| Septic fields very limited | 79.0% |
| Clay swell (LEP, by area) | 4.9% |
| High-swell land (LEP 6%+) | 29.4% |
| Mapped soil | 535,226 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Nuff | 12% | n/a |
| Real | 8% | n/a |
| Brackett | 8% | 0% |
| Krum | 7% | n/a |
| Doss | 6% | n/a |
| Pidcoke | 6% | n/a |
How we count · survey areas TX193 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 4.9% by land area here, and 29% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 31% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 31% of Hamilton County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 28.02 in, 5.40 in below the 1991-2020 average year of 33.42 in.
USDA rates 79% 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 19 of the last 52 weeks; the most was 100% of its area, in 7 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
FEMA's flood data list no flood losses in Hamilton County since 2016.
Rain
| Average year, 1991-2020 | 33.42 in |
| 12 months to August 2026 | 28.02 in (-5.40) |
| 2025 | 31.91 in (-1.51) |
| Wettest year since 1895 | 1919: 49.74 in |
| Driest year since 1895 | 1954: 15.10 in |
| Days with 1 inch or more, normal at CRANFILLS GAP (17 mi away) | 10 |
Homes
| Housing units | 4,372 |
| Median year built | 1965 |
| Built before 1980 | 69% |
| Built 2000 or later | 18% |
| Owner-occupied | 79% |
| Median value, owner-occupied | $147,700 |
| Single-family detached | 88% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Hamilton County
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Coryell County, TX | 29 mi | 26% | under 1% |
| Comanche County, TX | 31 mi | 30% | 11% |
| Bosque County, TX | 31 mi | 29% | 1% |
| Mills County, TX | 32 mi | 26% | under 1% |
| Lampasas County, TX | 36 mi | 20% | under 1% |
| Erath County, TX | 37 mi | 20% | 6% |
| Somervell County, TX | 41 mi | 13% | 4% |
| Brown County, TX | 52 mi | 40% | 1% |
Sources: USDA SSURGO (September 4, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status