Septic soil in Sheboygan County, WI, by the numbers

Very limited

Soil across 88.3% of Sheboygan County, WI rates "Very limited" in USDA's septic-absorption-field interpretation. Practically, that rules out a simple gravity system for most of the county - 88.3% of it sits in USDA's most-constrained bucket. Sheboygan County covers 511.519 square miles and counts 118,331 residents.

This is a county figure, not a parcel figure

Nothing about Sheboygan County, WI's SSURGO figure applies to a specific address - it's a county-wide average. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Sheboygan County.

System cost, conventional vs. engineered

Given Sheboygan 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, Sheboygan County, WI is the 1,434-most-constrained of 3,058 rated counties for septic soil. Within Wisconsin alone it ranks 47 of 72.

Further reading

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