Clark County, IL Shrink-Swell Risk

Clark County, IL's soil, for shrink-swell risk

Moderate

Clark County, IL: USDA's soil survey rates 73.8% of the county "Moderate" for shrink-swell potential (3.34% linear extensibility). 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.

What Clark County's reading doesn't cover

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

What it costs to find out, versus to ignore it

With Clark County, IL 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 Clark County, IL compares

Nationally, Clark County, IL is the 950-most-constrained of 3,085 rated counties for shrink-swell soil. Within Illinois alone it ranks 77 of 101. The county spans 501 square miles, home to 15,076 people.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. Rutland County, VT and Owen County, IN 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 Illinois

Every county in Illinois is on this site, including Ford County, IL and Edgar County, IL. The full underlying dataset is downloadable directly, one row per county.