Gallia County's SSURGO septic rating
Very limited
Gallia County, OH's SSURGO dominant class comes back "Very limited", covering 98.4% of the county. That reading means a conventional system is a poor bet here - 98.4% of Gallia County lands in the strictest "very limited" bucket USDA uses. The county spans 466.53 square miles, home to 28,886 people.
What this number does and doesn't tell you
USDA's survey covers the whole of Gallia County, OH at once, not any single address. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.
Gallia County: conventional vs. engineered cost
98.4% of Gallia 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.
Gallia County's rank among Ohio counties
Among the 3,058 rated counties on this site, Gallia County, OH ranks 187 most-constrained nationally, and 23 of 87 within Ohio.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems