St. Landry Parish, LA Shrink-Swell Risk
St. Landry Parish, LA's soil, for shrink-swell risk
High
St. Landry Parish, LA: USDA's soil survey rates 39.9% of the county "High" for shrink-swell potential (8.29% linear extensibility). This is enough movement to matter: a standard footing can hold up here, but usually only with real moisture management, not by default.
What St. Landry Parish's reading doesn't cover
Two lots a mile apart in St. Landry Parish can carry different soil, even though they share one countywide reading. The real answer for one lot is still a site-specific geotechnical report, running about $1,000-$5,000 (typically near $2,700).
What it costs to find out, versus to ignore it
St. Landry Parish's soil reading is exactly the case where a report before construction, or before cracks widen, pays for itself. The report ($1,000-$5,000) is what tells you whether St. Landry Parish's county-level reading applies to your lot; the repair ($5,000-$15,000) is what it costs if you skip that and find out from the cracks instead.
How St. Landry Parish, LA compares
Nationally, St. Landry Parish, LA is the 54-most-constrained of 3,085 rated counties for shrink-swell soil. Within Louisiana alone it ranks 22 of 64. St. Landry Parish covers 923 square miles and counts 80,869 residents.
Before you act on this
Orleans Parish, LA carries this site's most-constrained reading. Traverse County, MN and Forest County, PA are worth a look for comparison.
How this reading is built, and its real limits · The warning signs of expansive-clay damage, explained
More of Louisiana
Every county in Louisiana is on this site, including East Feliciana Parish, LA and Webster Parish, LA. The full underlying dataset is downloadable directly, one row per county.