States / North Dakota
53 counties · median score 24
Crawl space moisture in North Dakota
Most of North Dakota drains well: only 9 of 53 counties score high or elevated, and the median is 24. Pembina County is the exception at 56; crawl-space moisture problems here usually come from grading, gutters and plumbing rather than the soil itself.
- 1Wettest county Pembina County
- 2High or elevated 9 of 53
- 3Median score 24
- 4Driest county Golden Valley County
North Dakota's soil, taken as a whole
Across the 45,252,120 acres mapped in these 53 counties, 23% of soil with a drainage class is somewhat poorly, poorly or very poorly drained, and 57% of acres report a seasonal water table within about two metres. That is a middling figure: wet ground is common in valleys and lowlands but far from universal. 53 of the 53 counties have mapped soils subject to occasional or frequent flooding.
| Drainage class | Share of mapped acres |
|---|---|
| Excessively drained | 2.4% |
| Somewhat excessively drained | 3.7% |
| Well drained | 51.7% |
| Moderately well drained | 19.3% |
| Somewhat poorly drained | 11.8% |
| Poorly drained | 7.5% |
| Very poorly drained | 3.7% |
Radon. By EPA zone, 53 North Dakota counties here are zone 1 (highest potential), 0 zone 2 and 0 zone 3. With most of the state in zone 1, any crawl-space sealing project here should start with a radon test and be designed to take a radon fan.
Every North Dakota county
Sorted wettest first. High and elevated counties link to their own page with the full soil breakdown.
What drives the North Dakota numbers
The wettest county, Pembina County, is 40% somewhat poorly drained by dominant condition, with a seasonal water table averaging 2 ft below grade across the 97% of acres that report one, and sits in EPA radon zone 1. The driest, Golden Valley County, is 87% well drained. No North Dakota 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.