Buffalo County, SD Shrink-Swell Risk

What Buffalo County, SD's soil means for a foundation

Moderate

USDA's SSURGO data puts Buffalo County, SD's soil at "Moderate" shrink-swell potential, an area-weighted linear extensibility of 5.7% across 44% of the county's surveyed land. 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.

This is a county figure, not a lot figure

USDA's survey covers the whole of Buffalo County, SD at once, not any single address. 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 Buffalo County.

Report cost vs. repair cost

With Buffalo County, SD 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.

Buffalo County's rank among South Dakota counties

Nationally, Buffalo County, SD is the 186-most-constrained of 3,085 rated counties for shrink-swell soil. Within South Dakota alone it ranks 15 of 66. Buffalo County covers 471 square miles and counts 1,825 residents.

See how another county compares

Orleans Parish, LA carries this site's most-constrained reading. Shawnee County, KS and Allegheny 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

More of South Dakota

Every county in South Dakota is on this site, including Corson County, SD and Miner County, SD. The full underlying dataset is downloadable directly, one row per county.