Brazoria County, Texas
Shrink-swell clay limits houses without basements on 64% of Brazoria County's mapped land, a higher share than 95% of US counties. A shallow water table limits basements on 44%.
40.3% of the county is in drought on the September 22, 2026 Drought Monitor map, down from 44.6% a week earlier. FEMA's flood data list 6,507 flood losses here since 2016, under 1% of them in buildings with basements. 29% of homes were built before 1980, against 50% nationally; the median home dates from 1996.
Data as of September 22, 2026 · sources
expansive clay: shrink-swell limits slab homes
high water table: limits basements
in drought, September 22, 2026
of homes built before 1980
Soil under Brazoria County
| Expansive clay (limits slab homes) | 64.0% |
| High water table (limits basements) | 43.7% |
| Septic fields very limited | 75.2% |
| Clay swell (LEP, by area) | 10.9% |
| High-swell land (LEP 6%+) | 64.1% |
| Mapped soil | 951,468 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Lake Charles | 25% | 97% |
| Pledger | 12% | n/a |
| Bernard | 12% | 43% |
| Edna | 8% | n/a |
| Brazoria | 6% | n/a |
| Asa | 5% | 0% |
How we count · survey areas TX039 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 10.9% by land area here, and 64% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 64% of the mapped land.
Clay shrinks as it dries: 40.3% of the county is in drought on the latest map, and 64% of Brazoria County's mapped land has shrink-swell clay.
On 44% of Brazoria 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: 42.40 in, 8.02 in below the 1991-2020 average year of 50.42 in.
USDA rates 75% of the land very limited for septic absorption fields.
Drought
40.3% of the county is in drought (D1 or worse) on the September 22, 2026 map. Part of the county was in drought in 35 of the last 52 weeks; the most was 100% of its area, in 18 weeks, most recently on the May 5, 2026 map.
| Category, September 22, 2026 | Share of county |
|---|---|
| D0 abnormally dry or worse | 100% |
| D1 moderate drought or worse | 40.3% |
| D2 severe or worse | 0% |
| D3 extreme or worse | 0% |
| D4 exceptional | 0% |
Flood losses since 2016
6,507 flood losses since 2016, $449.5 million paid. The worst year was 2017, with 5,120. Foundations of the buildings, where recorded: under 1% basements, 81% slabs, 2% crawl spaces, 17% elevated. Median water depth outside the building: 15 in.
| Year | Flood losses |
|---|---|
| 2016 | 584 |
| 2017 | 5,120 |
| 2018 | 17 |
| 2019 | 128 |
| 2020 | 104 |
| 2021 | 166 |
| 2022 | 15 |
| 2023 | 9 |
| 2024 | 330 |
| 2025 | 7 |
| 2026 to date | 27 |
Rain
| Average year, 1991-2020 | 50.42 in |
| 12 months to August 2026 | 42.40 in (-8.02) |
| 2025 | 36.32 in (-14.10) |
| Wettest year since 1895 | 1973: 77.33 in |
| Driest year since 1895 | 1917: 20.42 in |
| Days with 1 inch or more, normal at FREEPORT 2 NW (13 mi away) | 16.9 |
Homes
| Housing units | 150,321 |
| Median year built | 1996 |
| Built before 1980 | 29% |
| Built 2000 or later | 45% |
| Owner-occupied | 74% |
| Median value, owner-occupied | $301,600 |
| Single-family detached | 73% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Brazoria County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Alvin | 65% | 48% | 12,327 |
| Angleton | 64% | 65% | 8,558 |
| Bailey's Prairie | 57% | 13% | 312 |
| Bonney | 74% | 21% | 142 |
| Brazoria | 28% | under 1% | 1,281 |
| Brookside Village | 69% | 56% | 542 |
| Clute | 47% | 28% | 5,229 |
| Danbury | 74% | 69% | 795 |
| Freeport | 49% | 75% | 5,078 |
| Hillcrest Village | 48% | 78% | 277 |
| Holiday Lakes | 38% | 2% | 333 |
| Iowa Colony | 76% | 28% | 4,683 |
| Jones Creek | 5% | 1% | 841 |
| Lake Jackson | 67% | 15% | 11,532 |
| Liverpool | 84% | 33% | 272 |
| Manvel | 70% | 47% | 5,283 |
| Oyster Creek | 48% | 27% | 662 |
| Pearland | 70% | 36% | 47,560 |
| Quintana | 3% | 30% | 29 |
| Richwood | 78% | 6% | 2,080 |
| Sandy Point | 74% | 34% | 81 |
| Surfside Beach | 13% | 93% | 1,208 |
| Sweeny | 36% | 2% | 1,624 |
| West Columbia | 35% | 42% | 1,522 |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Fort Bend County, TX | 32 mi | 64% | 42% |
| Galveston County, TX | 33 mi | 23% | 61% |
| Matagorda County, TX | 44 mi | 62% | 28% |
| Harris County, TX | 48 mi | 25% | 53% |
| Wharton County, TX | 49 mi | 68% | 32% |
| Chambers County, TX | 59 mi | 63% | 68% |
| Waller County, TX | 67 mi | 24% | 40% |
| Austin County, TX | 71 mi | 38% | 20% |
Sources: USDA SSURGO (September 4, 2025) · US Drought Monitor (September 22, 2026) · FEMA NFIP v3 (September 9, 2026) · NOAA (August 2026) · Census ACS 2020-2024. Methods · Data status