Jefferson County, AL Shrink-Swell Risk
Shrink-swell potential in Jefferson County, AL
Low
Soil across 94.5% of Jefferson County, AL comes back "Low" in USDA's shrink-swell data, averaging 1.35% 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 Jefferson County, AL - 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).
Jefferson County: the real numbers
Jefferson 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 Jefferson County, AL compares
Among the 3,085 rated counties on this site, Jefferson County, AL ranks 2,657 most-constrained nationally, and 59 of 67 within Alabama. Jefferson County, AL is 1,112 square miles with a population of 664,744.
See how another county compares
Orleans Parish, LA carries this site's most-constrained reading. Thurston County, WA and Winnebago County, IA 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 Alabama
Every county in Alabama is on this site, including DeKalb County, AL and Bullock County, AL. The full underlying dataset is downloadable directly, one row per county.