Calhoun County, Texas
Shrink-swell clay limits houses without basements on 33% of Calhoun County's mapped land, a higher share than 82% of US counties. A shallow water table limits basements on 31%.
100% of the county is in drought on the October 13, 2026 Drought Monitor map. FEMA's flood data list 336 flood losses here since 2016, 1% of them in buildings with basements. 53% of homes were built before 1980, against 50% nationally; the median home dates from 1978.
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 Calhoun County
| Expansive clay (limits slab homes) | 32.9% |
| High water table (limits basements) | 30.6% |
| Septic fields very limited | 47.9% |
| Clay swell (LEP, by area) | 7.0% |
| High-swell land (LEP 6%+) | 34.1% |
| Mapped soil | 584,893 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Laewest | 13% | 94% |
| Dacosta | 5% | n/a |
| Livia | 5% | n/a |
| Galveston | 3% | n/a |
| Arrada | 3% | n/a |
| Veston | 2% | n/a |
How we count · survey areas TX057 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 7.0% by land area here, and 34% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 33% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 33% of Calhoun County's mapped land has shrink-swell clay.
On 31% of Calhoun 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: 33.99 in, 5.36 in below the 1991-2020 average year of 39.35 in.
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 39 of the last 52 weeks; the most was 100% of its area, in 37 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 | 26.1% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
336 flood losses since 2016, $5.6 million paid. The worst year was 2017, with 270. Foundations of the buildings, where recorded: 1% basements, 69% slabs, 1% crawl spaces, 30% elevated. Median water depth outside the building: 10 in.
| Year | Flood losses |
|---|---|
| 2016 | 1 |
| 2017 | 270 |
| 2018 | 3 |
| 2019 | 3 |
| 2020 | 4 |
| 2021 | 38 |
| 2022 | 1 |
| 2023 | 4 |
| 2024 | 5 |
| 2025 | 7 |
| 2026 to date | 0 |
Rain
| Average year, 1991-2020 | 39.35 in |
| 12 months to August 2026 | 33.99 in (-5.36) |
| 2025 | 35.21 in (-4.14) |
| Wettest year since 1895 | 1960: 65.28 in |
| Driest year since 1895 | 1917: 11.87 in |
| Days with 1 inch or more, normal at PT COMFORT (15 mi away) | 12.9 |
Homes
| Housing units | 10,833 |
| Median year built | 1978 |
| Built before 1980 | 53% |
| Built 2000 or later | 24% |
| Owner-occupied | 77% |
| Median value, owner-occupied | $171,200 |
| Single-family detached | 73% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Calhoun County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Point Comfort | 89% | 13% | 155 |
| Port Lavaca | 65% | 8% | 5,394 |
| Seadrift | 74% | 39% | 801 |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Aransas County, TX | 32 mi | 18% | 35% |
| Victoria County, TX | 34 mi | 65% | 35% |
| Jackson County, TX | 36 mi | 67% | 24% |
| Refugio County, TX | 36 mi | 54% | 15% |
| Matagorda County, TX | 42 mi | 62% | 28% |
| Goliad County, TX | 54 mi | 24% | 21% |
| Wharton County, TX | 62 mi | 68% | 32% |
| San Patricio County, TX | 64 mi | 58% | 14% |
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