Riley County, KS Shrink-Swell Risk

Shrink-swell potential in Riley County, KS

Moderate

Soil across 50.4% of Riley County, KS comes back "Moderate" in USDA's shrink-swell data, averaging 5.59% 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 Riley County, KS - never a reading for one specific parcel. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in Riley County will actually do.

Riley County: the real numbers

Riley 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.

Where this sits nationally

Among the 3,085 rated counties on this site, Riley County, KS ranks 203 most-constrained nationally, and 34 of 105 within Kansas. The county spans 610 square miles, home to 72,557 people.

See how another county compares

Orleans Parish, LA carries this site's most-constrained reading. Edgar County, IL and Seminole County, FL 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 Kansas

Every county in Kansas is on this site, including Norton County, KS and Marion County, KS. The full underlying dataset is downloadable directly, one row per county.