What Keokuk County, IA's soil rates for a septic system
Very limited
In Keokuk County, IA, 99% 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. Keokuk County covers 579.175 square miles and counts 9,855 residents.
This is a county figure, not a parcel figure
Nothing about Keokuk County, IA'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 Keokuk County.
System cost, conventional vs. engineered
Given Keokuk 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.
Keokuk County's rank among Iowa counties
Nationally, Keokuk County, IA is the 100-most-constrained of 3,058 rated counties for septic soil. Within Iowa alone it ranks 6 of 99.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems