Silver Bow County, MT Shrink-Swell Risk
Shrink-swell potential in Silver Bow County, MT
Low
Soil across 84.9% of Silver Bow County, MT comes back "Low" in USDA's shrink-swell data, averaging 2.05% linear extensibility. That's the easiest starting point on this site's scale - a standard foundation is the reasonable default here, though any one lot can still differ.
What this number does and doesn't tell you
This is a countywide, area-weighted figure across every soil survey map unit in Silver Bow County, MT - never a reading for one specific parcel. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).
Silver Bow County: the real numbers
Silver Bow 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, Silver Bow County, MT ranks 1,938 most-constrained nationally, and 43 of 54 within Montana. The county spans 718 square miles, home to 36,134 people.
See how another county compares
Orleans Parish, LA carries this site's most-constrained reading. Lincoln County, ID and Westchester County, NY 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 Montana
Every county in Montana is on this site, including Madison County, MT and Wheatland County, MT. The full underlying dataset is downloadable directly, one row per county.