Sweet Grass County, MT Shrink-Swell Risk

What Sweet Grass County, MT's soil means for a foundation

Moderate

USDA's SSURGO data puts Sweet Grass County, MT's soil at "Moderate" shrink-swell potential, an area-weighted linear extensibility of 3.3% across 49.4% 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 Sweet Grass County, MT 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 Sweet Grass County.

Report cost vs. repair cost

With Sweet Grass County, MT 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.

Sweet Grass County's rank among Montana counties

Nationally, Sweet Grass County, MT is the 978-most-constrained of 3,085 rated counties for shrink-swell soil. Within Montana alone it ranks 29 of 54. Sweet Grass County covers 1,856 square miles and counts 3,757 residents.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Winnebago County, IL and Boundary County, ID 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 Montana

Every county in Montana is on this site, including McCone County, MT and Dawson County, MT. The full underlying dataset is downloadable directly, one row per county.