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Wallis, Texas
Inside Wallis' city limits, shrink-swell clay limits houses without basements on 86% of mapped land, the 2nd-highest of 7 cities in Austin County. A shallow water table limits basements on 61%, the highest of 7 cities in Austin County.
That clay share is above Austin County's 38%. FEMA's flood data list 189 flood losses since 2016 in ZIP code 77485 overlapping the city. Of its 865 homes, 48% were built before 1980; the median dates from 1981.
Data as of October 13, 2026 · sources · in Austin County
expansive clay: shrink-swell limits slab homes
high water table: limits basements
flood losses since 2016 in 1 overlapping ZIP
of homes built before 1980
Foundation repair in Wallis
Foundation repair in Wallis: shrink-swell clay limits slab homes on 86% of Wallis' mapped land, more than in 94% of Texas cities.
About 500 of Wallis' 865 homes are detached houses.
| Who designs the repair | The ASCE Texas Section's repair guidelines say a Texas-licensed engineer should evaluate the foundation and design the repair (2022 guidelines) |
| Prices | Cost guide ranges compared |
Soil under Wallis city limits
| Expansive clay (limits slab homes) | 85.8% |
| High water table (limits basements) | 61.5% |
| Septic fields very limited | 89.1% |
| Clay swell (LEP, by area) | 9.3% |
| High-swell land (LEP 6%+) | 85.8% |
| Mapped soil | 968 acres |
| Soil series | Share here | Series nationally: expansive clay |
|---|---|---|
| Verland | 56% | n/a |
| Lake Charles | 30% | 97% |
| Waller | 3% | n/a |
| Bernard | 2% | 43% |
| Edna | 1% | n/a |
| Cieno | under 1% | n/a |
What the numbers mean here
Clay swell averages a linear extensibility of 9.3% by land area here, and 86% of the land reaches USDA's high class (6% or more). Clay like that swells when wet and shrinks when dry, under 86% of the mapped land.
Clay shrinks as it dries: 96.2% of Austin County is in drought on the latest map, and 86% of Wallis' mapped land has shrink-swell clay.
On 61% of Wallis' mapped land, soil stays saturated within about 6 feet of the surface for part of the year, which is basement depth.
USDA rates 89% of the land very limited for septic absorption fields.
Drought in Austin County
96.2% of Austin County is in drought (D1 or worse) on the October 13, 2026 map. County detail.
Flood losses by ZIP code
FEMA flood records since 2016 in the ZIP codes that overlap Wallis. ZIP areas reach past city limits.
| ZIP | Share of city land | Flood losses | Paid |
|---|---|---|---|
| 77485 | 100% | 189 | $19.6 million |
Homes in Wallis
| Housing units | 865 |
| Median year built | 1981 |
| Built before 1980 | 48% |
| Built 2000 or later | 31% |
| Owner-occupied | 70% |
| Median value, owner-occupied | $157,200 |
| Single-family detached | 63% |
Nearby cities
| Place | Distance | Expansive clay | High water table |
|---|---|---|---|
| Orchard | 6 mi | 37% | 69% |
| Simonton | 6 mi | 41% | 2% |
| South Frydek | 7 mi | 90% | 12% |
| East Bernard | 7 mi | 74% | 36% |
| Weston Lakes | 8 mi | 32% | 6% |
| Brazos Country | 8 mi | 15% | 21% |
| Sealy | 11 mi | 10% | 32% |
| San Felipe | 11 mi | 56% | 36% |
Sources: USDA SSURGO (August 5, 2026) · US Drought Monitor (October 13, 2026) · FEMA NFIP v3 (September 9, 2026) · Census ACS 2020-2024. Methods · Data status