Septic soil in Wilson County, KS, by the numbers
Very limited
98.8% of Wilson County, KS's surveyed soil comes back "Very limited" in USDA's own SSURGO data, the county's dominant condition for a septic absorption field. This is the reading that pushes a project toward an engineered system rather than a conventional one, and it covers 98.8% of Wilson County's land. Wilson County, KS is 570.423 square miles with a population of 8,398.
What Wilson County's reading doesn't cover
USDA's survey covers the whole of Wilson County, KS at once, not any single address. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Wilson County will actually do.
What a system would cost here
With 98.8% of Wilson 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 Wilson County, KS compares
Nationally, Wilson County, KS is the 123-most-constrained of 3,058 rated counties for septic soil. Within Kansas alone it ranks 11 of 105.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems