Codington County, SD's soil, for a septic absorption field

Very limited

In Codington County, SD, 95.4% 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. Codington County, SD is 687.585 square miles with a population of 29,278.

What Codington County's reading doesn't cover

USDA's survey covers the whole of Codington County, SD 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 Codington County will actually do.

What a system would cost here

With 95.4% of Codington 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.

Codington County's rank among South Dakota counties

Nationally, Codington County, SD is the 614-most-constrained of 3,058 rated counties for septic soil. Within South Dakota alone it ranks 7 of 66.

Before you act on this

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