What Pierce County, WA's soil rates for a septic system

Very limited

In Pierce County, WA, 96.4% of the surveyed land carries a "Very limited" rating for a standard septic drain field. That reading means a conventional system is a poor bet here - 96.4% of Pierce County lands in the strictest "very limited" bucket USDA uses. Pierce County covers 1,668.025 square miles and counts 941,170 residents.

This is a county figure, not a parcel figure

Nothing about Pierce County, WA's SSURGO figure applies to a specific address - it's a county-wide average. A site-specific perc test, usually $750-$1,850, is what a health department will actually require before permitting a lot in Pierce County.

System cost, conventional vs. engineered

Given Pierce 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.

Pierce County's rank among Washington counties

Nationally, Pierce County, WA is the 461-most-constrained of 3,058 rated counties for septic soil. Within Washington alone it ranks 11 of 39.

Related guides

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