Off-Grid Living in Yamhill County, Oregon

I've been digging through Yamhill County's own planning, building, and sanitation pages to figure out what off-grid living actually looks like here, and the short version is: it's doable, but it runs through a real permit sequence, and a lot of the fine print is set by the State of Oregon rather than the county.

Zoning is countywide here, unlike some Oregon counties that have none. Yamhill County (via its Zoning Ordinance) carves the landscape into resource zones like Exclusive Farm Use, Agriculture/Forestry, and Forestry, plus residential zones. Minimum lot sizes swing wildly depending on zone, for example the AF-10 district sets a 10-acre minimum for new parcels, while the F-80 forestry district requires 80 acres. Farm dwellings carry extra tests around acreage and "high-value farmland" status. Notably, any attempt to shrink resource-zone lot minimums needs sign-off from the state Land Conservation and Development Commission, not just the county. Bottom line: check your specific parcel's zone before assuming what you can build.

Dwellings, tiny homes, RVs: the county's own definition of "dwelling" excludes travel trailers and similar accommodations, so an RV isn't a legal permanent residence in the eyes of Yamhill's zoning code. RV parks are a distinct, separately regulated land use. Manufactured/mobile homes have their own county code and require a placement permit, plus an approved sanitation system, before occupancy. A tiny home on a permanent foundation gets treated like a conventional dwelling and needs a standard county building permit. Cities inside the county (McMinnville, Newberg, Dayton, etc.) run their own separate rules.

Building permits: the county's Building Division issues permits, but only after land use approval, septic/sanitation approval, and driveway approval are in hand. The county says to allow real processing time for plan review. Permits within incorporated cities need extra city sign-off first.

Septic: Yamhill runs a two-step county Sanitarian process (site evaluation, then an installation permit) under state DEQ technical standards. Alternative Treatment Technology units are allowed but come with added certification and maintenance-contract requirements. Worth flagging: DEQ septic rules (statewide) are changing effective January 1, 2026, so double-check current requirements with the county Sanitarian.

Greywater and rainwater: I found no Yamhill-specific ordinance for either. These appear to fall back to Oregon DEQ's statewide programs, so confirm with the county Sanitarian whether local review is folded into the state process.

Wells: private wells are a state matter (Oregon Water Resources Department for construction/water rights, Oregon Health Authority for well safety guidance). I didn't find a distinct Yamhill County well-permitting office.

Off-grid utilities: nothing in the county's rules explicitly demands grid power or municipal water, but a building permit does require proof of an approved wastewater system, so full off-grid living is workable if your septic/water arrangements are documented and approved.