Ventura County, CA Shrink-Swell Risk
Shrink-swell potential in Ventura County, CA
Moderate
Soil across 50.2% of Ventura County, CA comes back "Moderate" in USDA's shrink-swell data, averaging 3.12% 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 Ventura County, CA - 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 Ventura County will actually do.
Ventura County: the real numbers
Ventura 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.
How Ventura County, CA compares
Among the 3,085 rated counties on this site, Ventura County, CA ranks 1,096 most-constrained nationally, and 21 of 58 within California. Ventura County covers 1,841 square miles and counts 835,427 residents.
Before you act on this
Orleans Parish, LA carries this site's most-constrained reading. Cherokee County, TX and Marion County, OH 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 Kern County, CA and Alpine County, CA. The full underlying dataset is downloadable directly, one row per county.