Harmon County, OK Shrink-Swell Risk

Shrink-swell potential in Harmon County, OK

Moderate

Soil across 62.6% of Harmon County, OK comes back "Moderate" in USDA's shrink-swell data, averaging 3.22% linear extensibility. A real but modest amount of movement - standard foundations usually hold up, but drainage and moisture control around the foundation still matter more than on low-risk soil.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Harmon County, OK - 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 Harmon County.

Harmon County: the real numbers

Harmon 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.

Harmon County's rank among Oklahoma counties

Among the 3,085 rated counties on this site, Harmon County, OK ranks 1,037 most-constrained nationally, and 42 of 77 within Oklahoma. Harmon County, OK is 537 square miles with a population of 2,315.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. Chautauqua County, KS and Livingston County, KY 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 Oklahoma

Every county in Oklahoma is on this site, including Latimer County, OK and Choctaw County, OK. The full underlying dataset is downloadable directly, one row per county.