States / West Virginia
30 counties · median score 11
Crawl space moisture in West Virginia
Most of West Virginia drains well: only 0 of 30 counties score high or elevated, and the median is 11. Marshall County is the exception at 27; crawl-space moisture problems here usually come from grading, gutters and plumbing rather than the soil itself.
- 1Wettest county Marshall County
- 2High or elevated 0 of 30
- 3Median score 11
- 4Driest county McDowell County
West Virginia's soil, taken as a whole
Across the 9,442,933 acres mapped in these 30 counties, 2% of soil with a drainage class is somewhat poorly, poorly or very poorly drained, and 16% of acres report a seasonal water table within about two metres. That is a dry figure; wet soils here are confined to river bottoms and wetlands. 30 of the 30 counties have mapped soils subject to occasional or frequent flooding.
| Drainage class | Share of mapped acres |
|---|---|
| Somewhat excessively drained | 2.4% |
| Well drained | 87.4% |
| Moderately well drained | 8.6% |
| Somewhat poorly drained | 0.6% |
| Poorly drained | 0.9% |
| Very poorly drained | 0.1% |
Radon. By EPA zone, 11 West Virginia counties here are zone 1 (highest potential), 15 zone 2 and 4 zone 3. EPA says to test regardless of zone; a sealed crawl space is the cheapest moment to add radon venting if a test calls for it.
Every West Virginia county
Sorted wettest first. High and elevated counties link to their own page with the full soil breakdown.
What drives the West Virginia numbers
The wettest county, Marshall County, is 52% moderately well drained by dominant condition, with a seasonal water table averaging 2.5 ft below grade across the 92% of acres that report one, and sits in EPA radon zone 1. The driest, McDowell County, is 99% well drained. No West Virginia county reaches the high tier.
The score is a guide to the soil, not to a house: a well-graded lot with working gutters in a high county can have a dry crawl space, and a bad downspout can flood one in a low county. The R408 calculator sizes venting or encapsulation for any footprint.
Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted; EPA Map of Radon Zones, county table (June 2024 JSON). Checked 2026-10-23.