Off-Grid Living in Wahkiakum County, Washington

I've been digging into Wahkiakum County, Washington, because it's one of those quiet corners of the state that doesn't fit the usual "county zoning" mold, and that matters a lot if you're thinking about going off-grid there.

Zoning is the big wrinkle here. Most of Wahkiakum County is unincorporated and, per the county itself, doesn't have zoning at all. The only place zoning exists is inside the Town of Cathlamet, which runs its own Title 19 zoning code. So if your land is out in the unincorporated county, you're not fighting a zoning map, but you're still not free of oversight: the county's Building and Planning Department still has to sign off on structures, septic, and land-use questions through the Comprehensive Plan and building codes.

Dwellings get sorted into two buckets by the county. If you want to live in something permanently, whether it's a stick-built house, a tiny house, or an RV, it needs a building permit, has to meet Washington's state energy code, needs plumbing and conditioned air, and needs potable water and an approved septic or sewer connection before the county Environmental Health Department will let the building permit through. If you just want a bunkhouse or shed with no plumbing and no permanent-residence intent, you can skip a lot of that, but you legally can't live there full-time. Manufactured homes need their own placement permit with foundation and anchoring specs.

Septic is handled by Wahkiakum County Health & Human Services, following the state's WAC 246-272 code. They require a design from a licensed designer or engineer, and test pits (three for new construction, two for repairs) spaced roughly 60 feet apart. Composting toilets aren't spelled out in any county-specific page I found, so I'd confirm directly with Environmental Health whether they'll accept one in place of a conventional system.

Greywater and rainwater harvesting don't have county-specific pages that I could find. That doesn't mean they're banned, it means the baseline is whatever Washington State's rules say (WAC 246-274 for greywater, Department of Ecology guidance for rainwater), and I'd call county Environmental Health to see if they layer anything extra on top.

Wells aren't handled by the county directly, that's Department of Ecology's water rights program, regionally covering Wahkiakum among a dozen other counties. But your well still has to satisfy the county's Environmental Health office before you can get a building permit for a permanent home.

Bottom line on full off-grid living: there's no ordinance banning it outright, but the permitting scheme for permanent residences effectively requires you to have approved water and septic hookups, so truly "disconnected" permanent living runs into that wall. A part-time cabin without plumbing sidesteps the requirement, but you give up the right to live there full-time.