Caldwell County, Texas
Shrink-swell clay limits houses without basements on 59% of Caldwell County's mapped land, a higher share than 94% of US counties. A shallow water table limits basements on 6%.
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. 34% of homes were built before 1980, against 50% nationally; the median home dates from 1991.
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 Caldwell County
| Expansive clay (limits slab homes) | 59.4% |
| High water table (limits basements) | 5.5% |
| Septic fields very limited | 85.2% |
| Clay swell (LEP, by area) | 8.0% |
| High-swell land (LEP 6%+) | 59.4% |
| Mapped soil | 349,556 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Crockett | 18% | 94% |
| Heiden | 10% | 80% |
| Branyon | 8% | 92% |
| Chaney | 7% | n/a |
| Houston Black | 6% | 91% |
| Patilo | 5% | n/a |
How we count · survey areas TX055 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 8.0% by land area here, and 59% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 59% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 59% of Caldwell County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 26.46 in, 8.99 in below the 1991-2020 average year of 35.45 in.
USDA rates 85% 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 52 of the last 52 weeks; the most was 100% of its area, in 43 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 | 100% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
6 flood losses since 2016, $74,990 paid. The worst year was 2017, with 3.
| Year | Flood losses |
|---|---|
| 2016 | 0 |
| 2017 | 3 |
| 2018 | 1 |
| 2019 | 0 |
| 2020 | 0 |
| 2021 | 0 |
| 2022 | 1 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 1 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 35.45 in |
| 12 months to August 2026 | 26.46 in (-8.99) |
| 2025 | 25.48 in (-9.97) |
| Wettest year since 1895 | 1919: 56.49 in |
| Driest year since 1895 | 1954: 14.76 in |
| Days with 1 inch or more, normal at LULING (11 mi away) | 11 |
Homes
| Housing units | 17,582 |
| Median year built | 1991 |
| Built before 1980 | 34% |
| Built 2000 or later | 38% |
| Owner-occupied | 75% |
| Median value, owner-occupied | $240,500 |
| Single-family detached | 61% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Caldwell County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Lockhart | 79% | under 1% | 5,865 |
| Luling | 75% | 3% | 2,671 |
| Martindale | 70% | under 1% | 443 |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Guadalupe County, TX | 26 mi | 52% | 8% |
| Bastrop County, TX | 27 mi | 52% | 14% |
| Gonzales County, TX | 27 mi | 55% | 5% |
| Travis County, TX | 28 mi | 39% | under 1% |
| Hays County, TX | 29 mi | 14% | under 1% |
| Comal County, TX | 38 mi | 19% | under 1% |
| Fayette County, TX | 43 mi | 67% | 14% |
| Lee County, TX | 52 mi | 48% | 25% |
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