Bastrop County, Texas
Shrink-swell clay limits houses without basements on 52% of Bastrop County's mapped land, a higher share than 91% of US counties. A shallow water table limits basements on 14%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 139 flood losses here since 2016, 0% of them in buildings with basements. 22% of homes were built before 1980, against 50% nationally; the median home dates from 1999.
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 Bastrop County
| Expansive clay (limits slab homes) | 51.8% |
| High water table (limits basements) | 14.0% |
| Septic fields very limited | 70.8% |
| Clay swell (LEP, by area) | 6.2% |
| High-swell land (LEP 6%+) | 51.8% |
| Mapped soil | 574,074 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Edge | 20% | n/a |
| Crockett | 14% | 94% |
| Padina | 11% | n/a |
| Tabor | 7% | n/a |
| Silstid | 4% | n/a |
| Robco | 4% | n/a |
How we count · survey areas TX021 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 6.2% by land area here, and 52% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 52% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 52% of Bastrop County's mapped land has shrink-swell clay.
Rain over the 12 months to August 2026: 28.75 in, 8.85 in below the 1991-2020 average year of 37.60 in.
USDA rates 71% 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 44 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
139 flood losses since 2016, $4.7 million paid. The worst year was 2016, with 93. Foundations of the buildings, where recorded: 79% slabs, 7% crawl spaces, 14% elevated. Median water depth outside the building: 12.5 in.
| Year | Flood losses |
|---|---|
| 2016 | 93 |
| 2017 | 40 |
| 2018 | 2 |
| 2019 | 0 |
| 2020 | 0 |
| 2021 | 3 |
| 2022 | 1 |
| 2023 | 0 |
| 2024 | 0 |
| 2025 | 0 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 37.60 in |
| 12 months to August 2026 | 28.75 in (-8.85) |
| 2025 | 31.48 in (-6.12) |
| Wettest year since 1895 | 1919: 57.49 in |
| Driest year since 1895 | 1954: 16.57 in |
| Days with 1 inch or more, normal at SMITHVILLE (11 mi away) | 12.3 |
Homes
| Housing units | 39,706 |
| Median year built | 1999 |
| Built before 1980 | 22% |
| Built 2000 or later | 49% |
| Owner-occupied | 77% |
| Median value, owner-occupied | $314,800 |
| Single-family detached | 67% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Bastrop County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Bastrop | 26% | 7% | 5,100 |
| Elgin | 83% | 4% | 4,493 |
| Smithville | 20% | 5% | 2,034 |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Travis County, TX | 25 mi | 39% | under 1% |
| Lee County, TX | 25 mi | 48% | 25% |
| Caldwell County, TX | 27 mi | 59% | 6% |
| Fayette County, TX | 28 mi | 67% | 14% |
| Williamson County, TX | 42 mi | 60% | 1% |
| Hays County, TX | 43 mi | 14% | under 1% |
| Gonzales County, TX | 45 mi | 55% | 5% |
| Burleson County, TX | 49 mi | 50% | 17% |
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