Comanche County, OK's soil, for a septic absorption field
Very limited
80.1% of Comanche County, OK'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 80.1% of Comanche County's land. Comanche County, OK is 1,069.322 square miles with a population of 121,396.
What Comanche County's reading doesn't cover
Two lots a mile apart in Comanche County can carry different soil, even though they share one countywide rating. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Comanche County will actually do.
What a system would cost here
With 80.1% of Comanche 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.
Where this sits nationally
Nationally, Comanche County, OK is the 2,035-most-constrained of 3,058 rated counties for septic soil. Within Oklahoma alone it ranks 52 of 77.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems