Skamania County's SSURGO septic rating

Very limited

Skamania County, WA: USDA's soil survey calls 91.4% of the county "Very limited" for a septic leach field. This is the reading that pushes a project toward an engineered system rather than a conventional one, and it covers 91.4% of Skamania County's land. The county spans 1,658.268 square miles, home to 12,660 people.

What this number does and doesn't tell you

Skamania County's rating is an average across the whole county, not a promise about any one lot inside it. Budget $750-$1,850 for a real perc test on any specific parcel - that's the only figure a permit application accepts.

Skamania County: conventional vs. engineered cost

91.4% of Skamania County carrying a "Very limited" reading changes the realistic budget here. Conventional systems run $3,000-$8,000 where they pass; where they don't, engineered alternatives (mound or aerobic treatment, whichever the health department requires) run $10,000-$40,000 - budget toward the higher figure until a perc test says otherwise.

Where this sits nationally

Among the 3,058 rated counties on this site, Skamania County, WA ranks 1,124 most-constrained nationally, and 20 of 39 within Washington.

Before you act on this

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