Marshall County, IA Shrink-Swell Risk

What Marshall County, IA's soil means for a foundation

Moderate

USDA's SSURGO data puts Marshall County, IA's soil at "Moderate" shrink-swell potential, an area-weighted linear extensibility of 4.13% across 87.9% of the county's surveyed land. Conventional foundations are the reasonable expectation here, with routine moisture-control practice rather than special engineering.

This is a county figure, not a lot figure

USDA's survey covers the whole of Marshall County, IA at once, not any single address. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in Marshall County will actually do.

Report cost vs. repair cost

With Marshall County, IA rating "Moderate", a geotechnical report is still worthwhile before a build, just less urgent than in a high-risk county. A geotechnical report runs $1,000-$5,000, typically around $2,700. Foundation repair, if a specific lot turns out to differ from the county average, runs $5,000-$15,000.

How Marshall County, IA compares

Nationally, Marshall County, IA is the 509-most-constrained of 3,085 rated counties for shrink-swell soil. Within Iowa alone it ranks 39 of 99. Marshall County covers 573 square miles and counts 40,392 residents.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. Starr County, TX and Yates County, NY are worth a look for comparison.

How this reading is built, and its real limits · Moisture management: the cheap fix that works on any soil

More of Iowa

Every county in Iowa is on this site, including Pocahontas County, IA and Warren County, IA. The full underlying dataset is downloadable directly, one row per county.