What Franklin County, ID's soil rates for a septic system

Very limited

In Franklin County, ID, 91.6% of the surveyed land carries a "Very limited" rating for a standard septic drain field. This is the reading that pushes a project toward an engineered system rather than a conventional one, and it covers 91.6% of Franklin County's land. Franklin County, ID is 663.019 square miles with a population of 15,638.

What Franklin County's reading doesn't cover

Nothing about Franklin County, ID's SSURGO figure applies to a specific address - it's a county-wide average. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Franklin County will actually do.

What a system would cost here

With 91.6% of Franklin County rating "Very limited", a standard gravity system is not a safe assumption here. 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.

How Franklin County, ID compares

Nationally, Franklin County, ID is the 1,100-most-constrained of 3,058 rated counties for septic soil. Within Idaho alone it ranks 12 of 44.

Before you act on this

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