What Union County, OR's soil rates for a septic system

Very limited

Soil across 94.7% of Union County, OR rates "Very limited" in USDA's septic-absorption-field interpretation. Expect the ground itself to work against a plain gravity system; USDA's strictest bucket alone covers 94.7% of the county. Union County covers 2,036.941 square miles and counts 26,058 residents.

This is a county figure, not a parcel figure

Union County's rating is an average across the whole county, not a promise about any one lot inside it. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Union County.

System cost, conventional vs. engineered

Given Union 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, Union County, OR is the 696-most-constrained of 3,058 rated counties for septic soil. Within Oregon alone it ranks 19 of 36.

Before you act on this

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