Boone County, IL Shrink-Swell Risk

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

Moderate

Boone County, IL: USDA's soil survey rates 79.9% of the county "Moderate" for shrink-swell potential (3.38% 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 Boone County's reading doesn't cover

Two lots a mile apart in Boone County can carry different soil, even though they share one countywide reading. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).

What it costs to find out, versus to ignore it

With Boone 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 Boone County, IL compares

Nationally, Boone County, IL is the 919-most-constrained of 3,085 rated counties for shrink-swell soil. Within Illinois alone it ranks 75 of 101. Boone County covers 281 square miles and counts 53,313 residents.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Ottawa County, OK and Newport County, RI 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 Jersey County, IL and Christian County, IL. The full underlying dataset is downloadable directly, one row per county.