Jefferson County, IA Shrink-Swell Risk

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

Moderate

Jefferson County, IA: USDA's soil survey rates 64.3% of the county "Moderate" for shrink-swell potential (5.32% linear extensibility). Conventional foundations are the reasonable expectation here, with routine moisture-control practice rather than special engineering.

What Jefferson County's reading doesn't cover

Two lots a mile apart in Jefferson 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 Jefferson County will actually do.

What it costs to find out, versus to ignore it

With Jefferson 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 Jefferson County, IA compares

Nationally, Jefferson County, IA is the 239-most-constrained of 3,085 rated counties for shrink-swell soil. Within Iowa alone it ranks 15 of 99. Jefferson County, IA is 436 square miles with a population of 15,781.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Hardin County, TX and Smith County, TX 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 Clay County, IA and Decatur County, IA. The full underlying dataset is downloadable directly, one row per county.