Macon County, IL Shrink-Swell Risk

Shrink-swell potential in Macon County, IL

Moderate

Soil across 91.7% of Macon County, IL comes back "Moderate" in USDA's shrink-swell data, averaging 4.28% 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 this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Macon 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 Macon County.

Macon County: the real numbers

Macon 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.

How Macon County, IL compares

Among the 3,085 rated counties on this site, Macon County, IL ranks 446 most-constrained nationally, and 16 of 101 within Illinois. Macon County, IL is 581 square miles with a population of 100,737.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Marion County, IL and Warren County, PA 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 Macoupin County, IL and Ogle County, IL. The full underlying dataset is downloadable directly, one row per county.