What Camas County, ID's soil rates for a septic system
Very limited
Soil across 96.2% of Camas County, ID rates "Very limited" in USDA's septic-absorption-field interpretation. That reading means a conventional system is a poor bet here - 96.2% of Camas County lands in the strictest "very limited" bucket USDA uses. Camas County covers 1,074.234 square miles and counts 1,247 residents.
This is a county figure, not a parcel figure
This is a countywide, area-weighted figure across every soil survey map unit in Camas County, ID - 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 Camas County.
System cost, conventional vs. engineered
Given Camas 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, Camas County, ID is the 507-most-constrained of 3,058 rated counties for septic soil. Within Idaho alone it ranks 5 of 44.
Further reading
How this rating is built, and its real limits · Conventional vs. engineered septic systems