Santa Clara County, CA Shrink-Swell Risk

Shrink-swell potential in Santa Clara County, CA

Moderate

Soil across 50.2% of Santa Clara County, CA comes back "Moderate" in USDA's shrink-swell data, averaging 3.67% linear extensibility. That's a middle reading: not the sharp swings that crack a foundation outright, but enough that grading and drainage are worth getting right.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Santa Clara County, CA - never a reading for one specific parcel. 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 Santa Clara County.

Santa Clara County: the real numbers

Santa Clara 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.

Santa Clara County's rank among California counties

Among the 3,085 rated counties on this site, Santa Clara County, CA ranks 744 most-constrained nationally, and 12 of 58 within California. The county spans 1,291 square miles, home to 1,926,325 people.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Vermillion County, IN and Yuma County, CO 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 California

Every county in California is on this site, including Madera County, CA and Monterey County, CA. The full underlying dataset is downloadable directly, one row per county.