Okanogan County, WA Shrink-Swell Risk

What Okanogan County, WA's soil means for a foundation

Low

USDA's SSURGO data puts Okanogan County, WA's soil at "Low" shrink-swell potential, an area-weighted linear extensibility of 1.58% across 96.6% of the county's surveyed land. That's as favorable a county-level reading as this dataset produces - standard foundation practice, pending one lot's own geotechnical report.

This is a county figure, not a lot figure

USDA's survey covers the whole of Okanogan County, WA at once, not any single address. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in Okanogan County will actually do.

Report cost vs. repair cost

With Okanogan County, WA rating "Low", 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.

Where this sits nationally

Nationally, Okanogan County, WA is the 2,401-most-constrained of 3,085 rated counties for shrink-swell soil. Within Washington alone it ranks 28 of 39. Okanogan County, WA is 5,266 square miles with a population of 44,942.

See how another county compares

Orleans Parish, LA carries this site's most-constrained reading. Lincoln County, ID and Quitman County, GA 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 Washington

Every county in Washington is on this site, including Lincoln County, WA and Kitsap County, WA. The full underlying dataset is downloadable directly, one row per county.