Yamhill County, OR Shrink-Swell Risk

Shrink-swell potential in Yamhill County, OR

Moderate

Soil across 56% of Yamhill County, OR comes back "Moderate" in USDA's shrink-swell data, averaging 3.68% linear extensibility. Conventional foundations are the reasonable expectation here, with routine moisture-control practice rather than special engineering.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Yamhill County, OR - never a reading for one specific parcel. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in Yamhill County will actually do.

Yamhill County: the real numbers

Yamhill 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, Yamhill County, OR ranks 732 most-constrained nationally, and 3 of 36 within Oregon. Yamhill County, OR is 716 square miles with a population of 110,886.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Cass County, ND and Pulaski County, MO 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 Oregon

Every county in Oregon is on this site, including Clatsop County, OR and Gilliam County, OR. The full underlying dataset is downloadable directly, one row per county.