Sanborn County, SD Shrink-Swell Risk

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

Moderate

USDA's SSURGO data puts Sanborn County, SD's soil at "Moderate" shrink-swell potential, an area-weighted linear extensibility of 3.55% across 57.8% 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 Sanborn County, SD at once, not any single address. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).

Report cost vs. repair cost

With Sanborn 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.

How Sanborn County, SD compares

Nationally, Sanborn County, SD is the 811-most-constrained of 3,085 rated counties for shrink-swell soil. Within South Dakota alone it ranks 56 of 66. Sanborn County covers 569 square miles and counts 2,392 residents.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. St. Lucie County, FL and Lincoln County, CO 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 Pennington County, SD and Lake County, SD. The full underlying dataset is downloadable directly, one row per county.