Grainger County's SSURGO septic rating

Very limited

USDA puts Grainger County, TN at "Very limited" for septic absorption fields, the dominant reading across 77% of the county's soil. That reading means a conventional system is a poor bet here - 77% of Grainger County lands in the strictest "very limited" bucket USDA uses. The county spans 280.587 square miles, home to 25,073 people.

What this number does and doesn't tell you

This is a countywide, area-weighted figure across every soil survey map unit in Grainger County, TN - never a reading for one specific parcel. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.

Grainger County: conventional vs. engineered cost

77% of Grainger 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.

Where this sits nationally

Among the 3,058 rated counties on this site, Grainger County, TN ranks 2,174 most-constrained nationally, and 64 of 95 within Tennessee.

Before you act on this

How this rating is built, and its real limits · Conventional vs. engineered septic systems