What a Septic System Costs in the Pacific Northwest
PNW Septic Guide Editorial · Reviewed September 2026
Why ranges are wide
Soil type, slope, setbacks, system design, access and county permitting all move the number significantly.
Typical categories
- Pumping: routine maintenance visit
- Inspection: visual versus comprehensive
- Minor repair: pumps, baffles, filters, lids
- Drainfield replacement: often the largest single cost short of full replacement
- New installation: conventional versus engineered or alternative treatment
Getting comparable quotes
Ask every contractor to quote the same scope, name the system design, and state what permitting is included.