Clarke County, IA Shrink-Swell Risk

Clarke County, IA's soil, for shrink-swell risk

Moderate

Clarke County, IA: USDA's soil survey rates 51.2% of the county "Moderate" for shrink-swell potential (5.69% linear extensibility). That's a middle reading: not the sharp swings that crack a foundation outright, but enough that grading and drainage are worth getting right.

What Clarke County's reading doesn't cover

Two lots a mile apart in Clarke County can carry different soil, even though they share one countywide reading. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in Clarke County will actually do.

What it costs to find out, versus to ignore it

With Clarke 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 Clarke County, IA compares

Nationally, Clarke County, IA is the 187-most-constrained of 3,085 rated counties for shrink-swell soil. Within Iowa alone it ranks 4 of 99. Clarke County, IA is 431 square miles with a population of 9,524.

See how another county compares

Orleans Parish, LA carries this site's most-constrained reading. Nuckolls County, NE and Columbus County, NC 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 Grundy County, IA and Scott County, IA. The full underlying dataset is downloadable directly, one row per county.