What Linn County, OR's soil rates for a septic system
Very limited
Soil across 95.7% of Linn County, OR rates "Very limited" in USDA's septic-absorption-field interpretation. That reading means a conventional system is a poor bet here - 95.7% of Linn County lands in the strictest "very limited" bucket USDA uses. Linn County, OR is 2,289.508 square miles with a population of 132,474.
What Linn County's reading doesn't cover
Nothing about Linn County, OR's SSURGO figure applies to a specific address - it's a county-wide average. A local percolation test, typically $750-$1,850 (around $1,300 typical), is the only way to know what one lot in Linn County will actually do.
What a system would cost here
With 95.7% of Linn 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, Linn County, OR is the 559-most-constrained of 3,058 rated counties for septic soil. Within Oregon alone it ranks 13 of 36.
Related guides
How this rating is built, and its real limits · Conventional vs. engineered septic systems