Septic soil in Marathon County, WI, by the numbers

Very limited

In Marathon County, WI, 85.6% of the surveyed land carries a "Very limited" rating for a standard septic drain field. Practically, that rules out a simple gravity system for most of the county - 85.6% of it sits in USDA's most-constrained bucket. Marathon County, WI is 1,545.249 square miles with a population of 139,091.

What Marathon County's reading doesn't cover

Nothing about Marathon County, WI'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 Marathon County will actually do.

What a system would cost here

With 85.6% of Marathon 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 Marathon County, WI compares

Nationally, Marathon County, WI is the 1,647-most-constrained of 3,058 rated counties for septic soil. Within Wisconsin alone it ranks 53 of 72.

Before you act on this

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