Off-Grid Living in Washington County, Minnesota

Washington County, Minnesota, is one of those places where the answer to "can I live off-grid here?" really depends on exactly where "here" is. The county's own zoning and Development Code, adopted under Minn. Stat. 394, only govern the unincorporated townships. Once you're inside a city like Stillwater, Woodbury, Cottage Grove, or Forest Lake, or an organized township that's adopted its own code (Lakeland, Scandia, and others), that local government is running the show on zoning and building permits, not the county. I can't stress this enough: before you buy land here, find out whether the parcel sits in unincorporated county territory or inside a municipal boundary, because the rules genuinely diverge.

For unincorporated land, the county's Development Code requires new parcels without public sewer to have at least one contiguous acre of buildable land, and generally limits you to one principal structure per parcel. On dwellings, the county is blunt: using a recreational vehicle, trailer, garage, cellar, or unfinished basement as a permanent dwelling unit is prohibited. Whether a tiny house on a permanent foundation would be treated as a legitimate dwelling isn't spelled out in what I found, so that's a question for the county's Zoning and Land Use Division or the relevant city/township office.

Building permits themselves are not issued by the county at all, full stop. The county's own permits page tells you to contact the city or township where the property sits. The county's direct role is septic (SSTS) permitting and access/driveway permits.

Septic is where Washington County is clearly and directly in charge, administering the state-mandated SSTS program through its Public Health and Environment Department. Design and installer licensing run through the county's Development Code, with some siting rules pulling from state Health Department rules. Notably, septic systems must be inspected at property transfer unless they're quite new, and the county does not do those inspections itself, you need a licensed inspector. Composting toilets aren't separately addressed in what I found; treat them as falling under the state's MPCA rules unless the county's SSTS ordinance says otherwise, and confirm with Public Health and Environment.

Greywater and rainwater harvesting have no standalone county ordinance that I could locate, so both likely default to state baseline rules (outdoor rain barrels are generally unregulated statewide; indoor plumbed systems trigger plumbing review). Wells are governed by the state's Well Code through the Minnesota Department of Health; the county's involvement mostly shows up around well-sealing when replacement funding is involved.

There's no explicit "you must hook up to the grid" ordinance in the county code, but a legal permanent dwelling still has to satisfy septic and building requirements regardless of whether it has grid power, so full off-grid living is achievable but not a free pass around code.