Black Hawk County, IA Shrink-Swell Risk

Shrink-swell potential in Black Hawk County, IA

Low

Soil across 51.6% of Black Hawk County, IA comes back "Low" in USDA's shrink-swell data, averaging 2.85% 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 this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Black Hawk County, IA - 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 Black Hawk County.

Black Hawk County: the real numbers

Black Hawk 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 Black Hawk County, IA compares

Among the 3,085 rated counties on this site, Black Hawk County, IA ranks 1,310 most-constrained nationally, and 93 of 99 within Iowa. Black Hawk County, IA is 566 square miles with a population of 132,348.

Before you act on this

Orleans Parish, LA carries this site's most-constrained reading. San Saba County, TX and Montgomery County, NY 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 Iowa

Every county in Iowa is on this site, including Delaware County, IA and Marion County, IA. The full underlying dataset is downloadable directly, one row per county.