Worth County, IA's soil, for a septic absorption field
Very limited
Soil across 94.3% of Worth County, IA rates "Very limited" in USDA's septic-absorption-field interpretation. This is the reading that pushes a project toward an engineered system rather than a conventional one, and it covers 94.3% of Worth County's land. Worth County covers 400.123 square miles and counts 7,307 residents.
This is a county figure, not a parcel figure
USDA's survey covers the whole of Worth County, IA at once, not any single address. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Worth County.
System cost, conventional vs. engineered
Given Worth 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.
Where this sits nationally
Nationally, Worth County, IA is the 749-most-constrained of 3,058 rated counties for septic soil. Within Iowa alone it ranks 54 of 99.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems