Lincoln County, ID's soil, for a septic absorption field

Very limited

86.9% of Lincoln County, ID's surveyed soil comes back "Very limited" in USDA's own SSURGO data, the county's dominant condition for a septic absorption field. Expect the ground itself to work against a plain gravity system; USDA's strictest bucket alone covers 86.9% of the county. Lincoln County covers 1,201.364 square miles and counts 5,556 residents.

This is a county figure, not a parcel figure

USDA's survey covers the whole of Lincoln County, ID at once, not any single address. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Lincoln County.

System cost, conventional vs. engineered

Given Lincoln County's rating, plan for the engineered-system range rather than the conventional one. The engineered-system range, $10,000-$40,000 (mound or aerobic treatment), is the more realistic number to plan around, against $3,000-$8,000 for a conventional system on the rare lot that passes.

Where this sits nationally

Nationally, Lincoln County, ID is the 1,553-most-constrained of 3,058 rated counties for septic soil. Within Idaho alone it ranks 26 of 44.

Before you act on this

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