Expansive Soil in West Virginia: County Ratings
3 of the 54 rated counties in West Virginia have a dominant shrink-swell rating of High or Very High. Each rating below is the NRCS shrink-swell class covering the largest share of the county's mapped soil acres, computed from USDA SSURGO data. Open a county for the full class breakdown and what it means for a slab foundation.
| County | Dominant class | High + Very High share | Survey coverage |
|---|---|---|---|
| Barbour County | Low | 0% | 99% |
| Berkeley County | Low | 7% | 97% |
| Boone County | Low | 0% | 99% |
| Braxton County | Low | 2% | 98% |
| Brooke County | Low | 1% | 76% * |
| Cabell County | Low | 1% | 94% |
| Calhoun County | Low | 22% | 99% |
| Clay County | Low | 0% | 99% |
| Doddridge County | Low | 0% | 99% |
| Fayette County | Low | 0% | 98% |
| Gilmer County | Low | 0% | 100% |
| Grant County | Low | 0% | 96% |
| Greenbrier County | Low | 8% | 99% |
| Hampshire County | Low | 0% | 99% |
| Hancock County | Low | 1% | 84% |
| Hardy County | Low | 0% | 98% |
| Harrison County | Low | 1% | 95% |
| Jackson County | High | 40% | 97% |
| Kanawha County | Low | 2% | 94% |
| Lewis County | Low | 0% | 96% |
| Lincoln County | Low | 2% | 99% |
| Logan County | Low | 0% | 97% |
| Marion County | Low | 0% | 98% |
| Marshall County | Moderate | 1% | 96% |
| Mason County | Low | 14% | 96% |
| McDowell County | Low | 0% | 100% |
| Mercer County | Low | 0% | 98% |
| Mineral County | Low | 0% | 98% |
| Mingo County | Low | 0% | 96% |
| Monongalia County | Low | 1% | 96% |
| Monroe County | Low | 12% | 99% |
| Morgan County | Low | 8% | 99% |
| Nicholas County | Low | 0% | 98% |
| Ohio County | Low | 1% | 85% |
| Pendleton County | Low | 2% | 100% |
| Pleasants County | Low | 5% | 94% |
| Pocahontas County | Low | 0% | 100% |
| Preston County | Low | 0% | 99% |
| Putnam County | Low | 17% | 97% |
| Raleigh County | Low | 0% | 97% |
| Randolph County | Low | 0% | 97% |
| Ritchie County | Low | 37% | 99% |
| Roane County | Low | 25% | 99% |
| Summers County | Moderate | 0% | 97% |
| Taylor County | Low | 0% | 97% |
| Tucker County | Low | 0% | 99% |
| Tyler County | Low | 5% | 98% |
| Upshur County | Low | 0% | 99% |
| Wayne County | Low | 6% | 97% |
| Webster County | Low | 0% | 99% |
| Wetzel County | Low | 0% | 99% |
| Wirt County | High | 50% | 99% |
| Wood County | High | 57% | 91% |
| Wyoming County | Low | 0% | 99% |
* Less than 80% of this county's map acres have completed soil survey data; treat its rating as provisional.
How these ratings are computed
Ratings come from USDA NRCS SSURGO soil survey data: for each soil component we take the maximum linear extensibility percent (lep_r) in the top 100 cm, apply the NRCS Handbook Part 618 class limits (Low under 3 percent, Moderate 3 to 6, High 6 to 9, Very High 9 and above), assign map units by plurality of component percent, and roll acres up to the county. Full details on the methodology section of the lookup page. A county rating is not a parcel-level geotechnical assessment.