Cameron County, Texas
Shrink-swell clay limits houses without basements on 29% of Cameron County's mapped land, a higher share than 79% of US counties. A shallow water table limits basements on 26%.
100% of the county is in drought on the September 22, 2026 Drought Monitor map. FEMA's flood data list 2,375 flood losses here since 2016, under 1% of them in buildings with basements. 30% of homes were built before 1980, against 50% nationally; the median home dates from 1992.
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 Cameron County
| Expansive clay (limits slab homes) | 29.0% |
| High water table (limits basements) | 26.1% |
| Septic fields very limited | 52.0% |
| Clay swell (LEP, by area) | 8.0% |
| High-swell land (LEP 6%+) | 33.3% |
| Urban land, not rated | 1.1% |
| Mapped soil | 747,821 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Laredo | 12% | 0% |
| Harlingen | 7% | n/a |
| Raymondville | 7% | n/a |
| Sejita | 6% | n/a |
| Lomalta | 5% | n/a |
| Willacy | 4% | n/a |
How we count · survey areas TX061 (2025-09-04)
What the numbers mean here
Clay swell averages a linear extensibility of 8.0% by land area here, and 33% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 29% of the mapped land.
Clay shrinks as it dries: 100% of the county is in drought on the latest map, and 29% of Cameron County's mapped land has shrink-swell clay.
On 26% of Cameron 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: 19.62 in, 5.95 in below the 1991-2020 average year of 25.57 in.
USDA rates 52% of the land very limited for septic absorption fields.
Drought
100% of the county is in drought (D1 or worse) on the September 22, 2026 map. Part of the county was in drought in 36 of the last 52 weeks; the most was 100% of its area, in 21 weeks, most recently on the September 22, 2026 map.
| Category, September 22, 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 | 100% |
| D4 exceptional | 44.9% |
Flood losses since 2016
2,375 flood losses since 2016, $135.5 million paid. The worst year was 2025, with 1,159. Foundations of the buildings, where recorded: under 1% basements, 88% slabs, 3% crawl spaces, 8% elevated. Median water depth outside the building: 11 in.
| Year | Flood losses |
|---|---|
| 2016 | 8 |
| 2017 | 17 |
| 2018 | 142 |
| 2019 | 700 |
| 2020 | 169 |
| 2021 | 137 |
| 2022 | 7 |
| 2023 | 4 |
| 2024 | 25 |
| 2025 | 1,159 |
| 2026 to date | 7 |
Rain
| Average year, 1991-2020 | 25.57 in |
| 12 months to August 2026 | 19.62 in (-5.95) |
| 2025 | 29.87 in (+4.30) |
| Wettest year since 1895 | 1941: 39.78 in |
| Driest year since 1895 | 1898: 7.70 in |
| Days with 1 inch or more, normal at BROWNSVILLE (13 mi away) | 7.2 |
Homes
| Housing units | 159,679 |
| Median year built | 1992 |
| Built before 1980 | 30% |
| Built 2000 or later | 38% |
| Owner-occupied | 65% |
| Median value, owner-occupied | $136,500 |
| Single-family detached | 65% |
What repairs cost
Published ranges from cost guides, not quotes. More sources, and where they disagree.
Cities in Cameron County
| City | Expansive clay | High water table | Homes |
|---|---|---|---|
| Bayview | 27% | 3% | 351 |
| Brownsville | 41% | 31% | 64,878 |
| Combes | 26% | 2% | 1,267 |
| Harlingen | 62% | 1% | 29,595 |
| Indian Lake | 15% | 0% | 465 |
| La Feria | 24% | under 1% | 3,396 |
| Laguna Vista | 34% | 64% | 1,924 |
| Los Fresnos | 45% | 10% | 2,600 |
| Los Indios | 41% | 1% | 289 |
| Palm Valley | 18% | 4% | 851 |
| Port Isabel | 7% | 54% | 2,661 |
| Primera | 18% | 3% | 1,798 |
| Rancho Viejo | 26% | 5% | 1,269 |
| Rangerville | 56% | 5% | 43 |
| Rio Hondo | 39% | 21% | 794 |
| San Benito | 63% | 4% | 9,367 |
| Santa Rosa | 50% | 2% | 1,002 |
| South Padre Island | 0% | 50% | 5,534 |
| Starbase | 8% | 49% | n/a |
Nearby counties
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Willacy County, TX | 27 mi | 18% | 34% |
| Hidalgo County, TX | 48 mi | 12% | 6% |
| Kenedy County, TX | 55 mi | 1% | 39% |
| Brooks County, TX | 79 mi | 1% | 9% |
| Starr County, TX | 84 mi | 14% | 1% |
| Kleberg County, TX | 93 mi | 31% | 18% |
| Jim Hogg County, TX | 102 mi | under 1% | under 1% |
| Nueces County, TX | 113 mi | 56% | 9% |
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