Septic soil in Cass County, MI, by the numbers

Very limited

93.8% of Cass County, MI'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 93.8% of the county. Cass County covers 490.129 square miles and counts 51,550 residents.

This is a county figure, not a parcel figure

This is a countywide, area-weighted figure across every soil survey map unit in Cass County, MI - never a reading for one specific parcel. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Cass County.

System cost, conventional vs. engineered

Given Cass 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.

How Cass County, MI compares

Nationally, Cass County, MI is the 816-most-constrained of 3,058 rated counties for septic soil. Within Michigan alone it ranks 40 of 83.

Further reading

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