Harper County, OK's soil, for a septic absorption field

Very limited

In Harper County, OK, 74.6% of the surveyed land carries a "Very limited" rating for a standard septic drain field. Expect the ground itself to work against a plain gravity system; USDA's strictest bucket alone covers 74.6% of the county. Harper County covers 1,038.584 square miles and counts 3,209 residents.

This is a county figure, not a parcel figure

This is a countywide, area-weighted figure across every soil survey map unit in Harper County, OK - never a reading for one specific parcel. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Harper County.

System cost, conventional vs. engineered

Given Harper 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, Harper County, OK is the 2,308-most-constrained of 3,058 rated counties for septic soil. Within Oklahoma alone it ranks 58 of 77.

Further reading

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