This page summarizes USDA SSURGO mapped soil information for Polk County, Iowa.
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 |
|---|---|---|---|
| L138B | Clarion loam, Bemis moraine, 2 to 6 percent slopes | 46,322.27 | 12.23% |
| L107 | Webster clay loam, Bemis moraine, 0 to 2 percent slopes | 31,729.7 | 8.38% |
| L55 | Nicollet loam, 1 to 3 percent slopes | 30,169.73 | 7.96% |
| L507 | Canisteo clay loam, Bemis moraine, 0 to 2 percent slopes | 26,321.13 | 6.95% |
| 4000 | Urban land | 15,237.98 | 4.02% |
| L138C2 | Clarion loam, Bemis moraine, 6 to 10 percent slopes, moderately eroded | 13,244.26 | 3.5% |
| W | Water | 11,731.03 | 3.1% |
| 135 | Coland clay loam, 0 to 2 percent slopes, occasionally flooded | 11,190.46 | 2.95% |
| 1820 | Dockery-Quiver silt loams, 0 to 2 percent slopes, occasionally flooded | 10,385.28 | 2.74% |
| 4138B | Clarion-Urban land complex, 2 to 5 percent slopes | 9,724.17 | 2.57% |
| 1585 | Spillville-Coland complex, channeled, 0 to 2 percent slopes | 8,857.98 | 2.34% |
| 4138C | Clarion-Urban land complex, 5 to 9 percent slopes | 6,846.3 | 1.81% |
| 485 | Spillville loam, 0 to 2 percent slopes, occasionally flooded | 6,278.6 | 1.66% |
| 11B | Colo-Judson silty clay loams, 0 to 5 percent slopes, occasionally flooded | 6,227.41 | 1.64% |
| L236B | Lester loam, Bemis moraine, 2 to 6 percent slopes | 5,714.7 | 1.51% |
| Component | Drainage Class | Hydrologic Group | Estimated Acres | % of Mapped Area |
|---|---|---|---|---|
| Clarion | Well drained | B | 70,735.97 | 18.67% |
| Webster | Poorly drained | C/D | 32,243.54 | 8.51% |
| Nicollet | Somewhat poorly drained | C/D, B/D | 31,793.38 | 8.39% |
| Urban land | Unspecified | Unspecified | 31,367.91 | 8.28% |
| Canisteo | Poorly drained | C/D | 23,397.85 | 6.18% |
| Coland | Poorly drained | C/D | 16,322.58 | 4.31% |
| Storden | Well drained | B | 12,127.41 | 3.2% |
| Spillville | Somewhat poorly drained, Moderately well drained | B, B/D | 12,087.45 | 3.19% |
| Water | Unspecified | Unspecified | 11,762.7 | 3.11% |
| Lester | Well drained | C | 10,101.23 | 2.67% |
| Colo | Poorly drained, Moderately well drained | C/D, B | 9,284.79 | 2.45% |
| Tama | Well drained | C | 8,592.04 | 2.27% |
| Hayden | Well drained | C, B | 7,841.27 | 2.07% |
| Sharpsburg | Moderately well drained | C | 7,683.78 | 2.03% |
| Downs | Well drained | C | 7,355.29 | 1.94% |
Hydrologic soil groups are USDA/NRCS classifications related to runoff potential under specified soil conditions. They are not a property-level flood-risk rating.