Davison County, SD: the USDA septic-suitability picture

Very limited

USDA puts Davison County, SD at "Very limited" for septic absorption fields, the dominant reading across 96.8% of the county's soil. Expect the ground itself to work against a plain gravity system; USDA's strictest bucket alone covers 96.8% of the county. For scale: 435.633 square miles and 19,907 people call Davison County home.

Before you rely on this for one lot

Two lots a mile apart in Davison County can carry different soil, even though they share one countywide rating. The real answer for one lot is still a site-specific perc test, running about $750-$1,850 (typically near $1,300).

Budgeting for a system in Davison County, SD

Davison County's soil reading pushes the likely outcome toward an engineered system rather than a conventional one. Conventional systems run $3,000-$8,000 where they pass; where they don't, engineered alternatives (mound or aerobic treatment, whichever the health department requires) run $10,000-$40,000 - budget toward the higher figure until a perc test says otherwise.

Where this sits nationally

Among the 3,058 rated counties on this site, Davison County, SD ranks 403 most-constrained nationally, and 4 of 66 within South Dakota.

Further reading

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