Washakie County's SSURGO septic rating
Very limited
Washakie County, WY's SSURGO dominant class comes back "Very limited", covering 68.2% of the county. A standard gravity system routinely fails on ground like this; the same share of the county falls in USDA's worst absorption-field bucket outright. The county spans 2,238.679 square miles, home to 7,662 people.
What this number does and doesn't tell you
Two lots a mile apart in Washakie County can carry different soil, even though they share one countywide rating. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.
Washakie County: conventional vs. engineered cost
68.2% of Washakie County carrying a "Very limited" reading changes the realistic budget here. Conventional systems run $3,000-$8,000 where they pass; where they don't, engineered alternatives (mound or aerobic treatment, whichever the health department requires) run $10,000-$40,000 - budget toward the higher figure until a perc test says otherwise.
How Washakie County, WY compares
Among the 3,058 rated counties on this site, Washakie County, WY ranks 2,526 most-constrained nationally, and 10 of 22 within Wyoming.
Further reading
How this rating is built, and its real limits · Conventional vs. engineered septic systems