Coles County, IL Shrink-Swell Risk

Shrink-swell potential in Coles County, IL

Moderate

Soil across 84.6% of Coles County, IL comes back "Moderate" in USDA's shrink-swell data, averaging 3.76% linear extensibility. Conventional foundations are the reasonable expectation here, with routine moisture-control practice rather than special engineering.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Coles County, IL - never a reading for one specific parcel. 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 Coles County.

Coles County: the real numbers

Coles County's soil reading points toward standard foundation practice as the likely outcome, not the exception. 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.

Coles County's rank among Illinois counties

Among the 3,085 rated counties on this site, Coles County, IL ranks 694 most-constrained nationally, and 41 of 101 within Illinois. Coles County covers 508 square miles and counts 46,423 residents.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. Clay County, MO and Danville city, VA 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

Elsewhere in Illinois

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