Nassau County, NY Shrink-Swell Risk

What Nassau County, NY's soil means for a foundation

Low

USDA's SSURGO data puts Nassau County, NY's soil at "Low" shrink-swell potential, an area-weighted linear extensibility of 1.22% across 100% of the county's surveyed land. 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.

This is a county figure, not a lot figure

USDA's survey covers the whole of Nassau County, NY at once, not any single address. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).

Report cost vs. repair cost

With Nassau County, NY 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, Nassau County, NY is the 2,755-most-constrained of 3,085 rated counties for shrink-swell soil. Within New York alone it ranks 39 of 62. Nassau County covers 285 square miles and counts 1,392,438 residents.

For contrast

Orleans Parish, LA carries this site's most-constrained reading. Dewey County, OK and Yellowstone County, MT 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 New York

Every county in New York is on this site, including Schoharie County, NY and Orleans County, NY. The full underlying dataset is downloadable directly, one row per county.