What Dane County, WI's soil rates for a septic system
Very limited
In Dane County, WI, 88.2% of the surveyed land carries a "Very limited" rating for a standard septic drain field. A standard gravity system routinely fails on ground like this; the same share of the county falls in USDA's worst absorption-field bucket outright. Dane County, WI is 1,196.496 square miles with a population of 588,347.
What Dane County's reading doesn't cover
Two lots a mile apart in Dane County can carry different soil, even though they share one countywide rating. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Dane County will actually do.
What a system would cost here
With 88.2% of Dane 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 Dane County, WI compares
Nationally, Dane County, WI is the 1,441-most-constrained of 3,058 rated counties for septic soil. Within Wisconsin alone it ranks 48 of 72.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems