Mercer County, PA Shrink-Swell Risk
Shrink-swell potential in Mercer County, PA
Low
Soil across 99.9% of Mercer County, PA comes back "Low" in USDA's shrink-swell data, averaging 1.38% linear extensibility. Among the 3,144 counties on this site, that's the clean result: little shrink-swell movement, standard construction the likely outcome.
What this number does and doesn't tell you
This is a countywide, area-weighted figure across every soil survey map unit in Mercer County, PA - never a reading for one specific parcel. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).
Mercer County: the real numbers
Mercer 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, Mercer County, PA ranks 2,627 most-constrained nationally, and 47 of 67 within Pennsylvania. Mercer County covers 673 square miles and counts 108,140 residents.
See how another county compares
Orleans Parish, LA carries this site's most-constrained reading. Johnston County, OK and Montgomery County, AR 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 Pennsylvania
Every county in Pennsylvania is on this site, including Snyder County, PA and Blair County, PA. The full underlying dataset is downloadable directly, one row per county.