This page summarizes USDA SSURGO mapped soil information for Dallas County, Texas.
The largest mapped unit is Houston Black-Urban land complex, 0 to 4 percent slopes (45), covering 11.61% of the mapped soil area shown here. Other leading units include Houston Black clay, 1 to 3 percent slopes (5.4%) and Trinity clay, 0 to 1 percent slopes, frequently flooded (4.67%).
Map-unit acreage and percentages describe mapped SSURGO soil area in the county. Component rows estimate the acreage of named soils by applying each component’s SSURGO proportion to mapped unit area; those components are not separately drawn polygon boundaries. The largest estimate is Urban land (14.6% of mapped area).
Drainage classes describe how quickly excess water is removed from soil, while hydrologic soil groups classify runoff potential under specified conditions. Neither is a parcel-level verdict. The coverage percentage below compares mapped soil area with Census county land area. For a particular address, use the lookup below and review its location-level sources.
This county summary is not an interactive map. The USDA NRCS tool opens separately; choose Texas and Dallas County in Quick Navigation, then define an Area of Interest before viewing soil maps or reports.
Coverage measures mapped SSURGO intersection with Census land geometry. It does not mean that every parcel or point has complete soil information.
County summaries provide regional context across mapped soil units. Address lookup combines available public datasets for the Census-matched location.
| Symbol | Map Unit Name | Mapped Acres | % of Mapped Area |
|---|---|---|---|
| 45 | Houston Black-Urban land complex, 0 to 4 percent slopes | 64,902.87 | 11.61% |
| 44 | Houston Black clay, 1 to 3 percent slopes | 30,183.29 | 5.4% |
| 73 | Trinity clay, 0 to 1 percent slopes, frequently flooded | 26,078.27 | 4.67% |
| 34 | Ferris-Heiden complex, 5 to 12 percent slopes | 24,855.47 | 4.45% |
| 8 | Austin-Urban land complex, 0 to 2 percent slopes | 19,293.02 | 3.45% |
| 5 | Austin silty clay, 1 to 3 percent slopes | 16,368.7 | 2.93% |
| 69 | Stephen-Urban land complex, 1 to 4 percent slopes | 16,222.47 | 2.9% |
| 42 | Heiden clay, 2 to 5 percent slopes, moderately eroded | 15,348.98 | 2.75% |
| 74 | Trinity-Urban land complex, 0 to 1 percent slopes, occasionally flooded | 15,049.61 | 2.69% |
| 72 | Trinity clay, 0 to 1 percent slopes, occasionally flooded | 14,995.56 | 2.68% |
| 75 | Urban land | 13,868.64 | 2.48% |
| 17 | Branyon clay, 0 to 1 percent slopes | 13,829.35 | 2.47% |
| 24 | Dalco-Urban land complex, 0 to 3 percent slopes | 13,776.94 | 2.47% |
| 9 | Austin-Urban land complex, 2 to 5 percent slopes | 12,690.44 | 2.27% |
| 30 | Eddy-Stephen complex, 1 to 5 percent slopes | 12,443.09 | 2.23% |
| Component | Drainage Class | Hydrologic Group | Estimated Acres | % of Mapped Area |
|---|---|---|---|---|
| Urban land | Well drained | D | 81,603.51 | 14.6% |
| Houston Black | Moderately well drained | D | 71,210.14 | 12.74% |
| Trinity | Moderately well drained | D | 45,275.95 | 8.1% |
| Austin | Well drained | C, D | 38,306.2 | 6.85% |
| Eddy | Well drained | D | 31,674.65 | 5.67% |
| Heiden | Well drained | D | 31,437.39 | 5.63% |
| Unnamed | Unspecified | Unspecified | 26,177.36 | 4.68% |
| Ferris | Well drained | D | 23,615.75 | 4.23% |
| Frio | Well drained | C | 21,063.87 | 3.77% |
| Stephen | Well drained | D | 20,476.94 | 3.66% |
| Lewisville | Well drained | C, B | 16,776.59 | 3% |
| Arents | Well drained | C, A, B | 15,965.99 | 2.86% |
| Wilson | Moderately well drained | C, D | 13,907.75 | 2.49% |
| Branyon | Moderately well drained | D | 12,583.29 | 2.25% |
| Dalco | Moderately well drained | D | 11,918.02 | 2.13% |
Hydrologic soil groups are USDA/NRCS classifications related to runoff potential under specified soil conditions. They are not a property-level flood-risk rating.