Minnesota / Pipestone County

Score 35 · moderate · #69 of 87 in MN

Crawl space moisture in Pipestone County, MN

Pipestone County scores moderate: no single wet-soil signal dominates its mapped acres. Where a seasonal water table is reported — 75% of acres — it averages 2 ft below grade.

Size venting or encapsulation

1234
  1. 1Water table 2 ft
  2. 2Wet soils 25%
  3. 3Moisture score 35
  4. 4EPA radon zone 1
Excessively1%Somewhat excessively2%Well49%Moderately well23%Somewhat poorly2%Poorly21%Very poorly1%
Share of mapped soil acres in Pipestone County, MN by NRCS drainage class (dominant condition), bars to scale; wetter classes highlighted. Covers 100% of mapped acres.
Dominant drainage
Well drained
49% of acres
Group D soils
23%
slow infiltration
Flood-prone acres
8%
any flooding frequency
Ponding
16.8%
acres where water ponds

Reading the Pipestone County soil survey

The score of 35 combines four parts, each from the USDA survey: wet drainage classes contribute 31.7 points of 100 on their own scale, group D soils 33.3, a shallow water table 52.5, and flooding 7.4; the weights are on the methodology page. The dominant hydrologic group is C (64% of acres): slow infiltration (clay layers).

2%A11%B64%C20%B/D3%C/D
Hydrologic soil groups in Pipestone County by share of acres, columns to scale. Group D and dual groups (x/D) shed water slowly and hold it near the surface.

At 2 ft the seasonal water table is usually below a crawl-space floor, but the 75% of acres that report one are by definition the wettest parts of the county; on those lots, a wet spring can bring water close to the footings.

Pipestone County against the rest of Minnesota

Pipestone County ranks 69 of 87 Minnesota counties, 12 points below the state median of 47. That places it in the middle range, nationally and for the state. Statewide, 55% of mapped soil is in the wet drainage classes; here it is 25%, below the state figure — the score here comes from a shallow water table rather than drainage class alone. After well drained, the next most common class is moderately well drained at 23%.

Flooding. 5.9% of acres with a flooding class are rated frequent; 2.5% of acres with a flooding class are rated occasional. Flood-prone soils are a minority here, concentrated along streams; the score mostly reflects what happens between floods. Ponding — water standing at the surface with nowhere to go — affects 16.8% of acres.

What it means for a crawl space here

In a moderate county the soil record is mixed rather than uniformly wet, so conditions vary from lot to lot. Where the lot drains, the model-code default — a vented crawl space with 1 sq ft of net vent per 150 sq ft of floor, or 1 per 1500 with a Class I vapor retarder on the ground — is a reasonable starting point; where the sections above point to a shallow water table or flood-prone soil on your lot, plan as for an elevated county. Either way, check the site first: grading that falls away from the foundation, gutters and downspouts that discharge well clear of it, and a ground cover over bare earth. A wet crawl space in a moderate county points to one of those first.

Radon. Pipestone County is in EPA radon zone 1, the highest predicted potential. A sealed crawl space and a radon system share most of their parts — the liner, the sealed seams, a fan — so if you are encapsulating, test for radon first and design both together. EPA itself says the zone map is not a reason to skip testing in zones 2 and 3.

Near Pipestone County by score

All 87 Minnesota counties

Sources: USDA NRCS SSURGO via Soil Data Access (muaggatt: drclassdcd, hydgrpdcd, flodfreqdcd, pondfreqprs, wtdepannmin), acreage-weighted (survey area MN117; drainage covers 100% of 298,300 mapped acres); EPA Map of Radon Zones, county table (June 2024 JSON); IRC R408.3 Unvented crawl space, as adopted in S.C. Code Regs. 8-1221 (LII). Checked 2026-10-23.