Lewis County, WA Shrink-Swell Risk

Lewis County, WA's soil, for shrink-swell risk

Low

Lewis County, WA: USDA's soil survey rates 69.8% of the county "Low" for shrink-swell potential (2.26% 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 Lewis County's reading doesn't cover

Two lots a mile apart in Lewis County can carry different soil, even though they share one countywide reading. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).

What it costs to find out, versus to ignore it

With Lewis 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.

How Lewis County, WA compares

Nationally, Lewis County, WA is the 1,747-most-constrained of 3,085 rated counties for shrink-swell soil. Within Washington alone it ranks 6 of 39. Lewis County, WA is 2,403 square miles with a population of 87,049.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. Magoffin County, KY and Halifax County, VA 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 King County, WA. The full underlying dataset is downloadable directly, one row per county.