Mariposa County, CA Shrink-Swell Risk

Mariposa County, CA's soil, for shrink-swell risk

Low

Mariposa County, CA: USDA's soil survey rates 83.6% of the county "Low" for shrink-swell potential (2.31% linear extensibility). That's as favorable a county-level reading as this dataset produces - standard foundation practice, pending one lot's own geotechnical report.

What Mariposa County's reading doesn't cover

Two lots a mile apart in Mariposa County can carry different soil, even though they share one countywide reading. A local geotechnical report, typically $1,000-$5,000 (around $2,700 typical), is the only way to know what one lot in Mariposa County will actually do.

What it costs to find out, versus to ignore it

With Mariposa County, CA 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, Mariposa County, CA is the 1,719-most-constrained of 3,085 rated counties for shrink-swell soil. Within California alone it ranks 43 of 58. The county spans 1,449 square miles, home to 17,048 people.

See how another county compares

Orleans Parish, LA carries this site's most-constrained reading. Divide County, ND and Alachua County, FL 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 California

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