Audubon County, IA Shrink-Swell Risk

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

Moderate

USDA's SSURGO data puts Audubon County, IA's soil at "Moderate" shrink-swell potential, an area-weighted linear extensibility of 4.48% across 94.4% of the county's surveyed land. A real but modest amount of movement - standard foundations usually hold up, but drainage and moisture control around the foundation still matter more than on low-risk soil.

This is a county figure, not a lot figure

USDA's survey covers the whole of Audubon County, IA at once, not any single address. A site-specific soil report, usually $1,000-$5,000, is what an engineer would actually pull before designing a foundation on a lot in Audubon County.

Report cost vs. repair cost

With Audubon 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.

Where this sits nationally

Nationally, Audubon County, IA is the 393-most-constrained of 3,085 rated counties for shrink-swell soil. Within Iowa alone it ranks 32 of 99. Audubon County covers 443 square miles and counts 5,562 residents.

See how another county compares

Orleans Parish, LA carries this site's most-constrained reading. Warren County, NY and Valencia County, NM 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 Plymouth County, IA and Tama County, IA. The full underlying dataset is downloadable directly, one row per county.