Somervell County, Texas
Shrink-swell clay limits houses without basements on 13% of Somervell County's mapped land, a higher share than 59% of US counties. A shallow water table limits basements on 4%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 6 flood losses here since 2016. 28% of homes were built before 1980, against 50% nationally; the median home dates from 1995.
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 Somervell County
| Expansive clay (limits slab homes) | 12.7% |
| High water table (limits basements) | 4.0% |
| Septic fields very limited | 65.4% |
| Clay swell (LEP, by area) | 4.8% |
| High-swell land (LEP 6%+) | 16.3% |
| Mapped soil | 122,681 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Eckrant | 24% | 8% |
| Purves | 12% | 40% |
| Sunev | 8% | n/a |
| Windthorst | 7% | 37% |
| Brackett | 5% | 0% |
| Bastrop | 4% | n/a |
How we count · survey areas TX609 (2025-09-05)
What the numbers mean here
Rain over the 12 months to August 2026: 27.23 in, 8.56 in below the 1991-2020 average year of 35.79 in.
USDA rates 65% of the land very limited for septic absorption fields.
With shrink-swell clay on 13% and a shallow water table on 4% of the land, the soil survey points to neither problem across most of Somervell 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 25 of the last 52 weeks; the most was 100% of its area, in 19 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 | 15.2% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
6 flood losses since 2016, $213,449 paid. The worst year was 2016, with 4.
| Year | Flood losses |
|---|---|
| 2016 | 4 |
| 2017 | 0 |
| 2018 | 0 |
| 2019 | 0 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 0 |
| 2023 | 1 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 1 |
Rain
| Average year, 1991-2020 | 35.79 in |
| 12 months to August 2026 | 27.23 in (-8.56) |
| 2025 | 39.32 in (+3.53) |
| Wettest year since 1895 | 2015: 63.24 in |
| Driest year since 1895 | 1901: 18.13 in |
| Days with 1 inch or more, normal at RAINBOW (5 mi away) | 10.1 |
Homes
| Housing units | 4,017 |
| Median year built | 1995 |
| Built before 1980 | 28% |
| Built 2000 or later | 41% |
| Owner-occupied | 80% |
| Median value, owner-occupied | $289,500 |
| Single-family detached | 68% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Somervell County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Glen Rose | 15% | under 1% | 1,231 |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Hood County, TX | 15 mi | 18% | 9% |
| Bosque County, TX | 23 mi | 29% | 1% |
| Johnson County, TX | 26 mi | 51% | 4% |
| Erath County, TX | 26 mi | 20% | 6% |
| Parker County, TX | 39 mi | 21% | 5% |
| Hamilton County, TX | 41 mi | 31% | under 1% |
| Hill County, TX | 41 mi | 53% | 2% |
| Tarrant County, TX | 47 mi | 41% | 4% |
Sources: USDA SSURGO (September 5, 2025) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status