Off-Grid Living in Granite County, Montana

Granite County, Montana is about as light-touch as it gets for off-grid living in the Lower 48, but "light-touch" doesn't mean "no rules." Here's what I found digging through the county's own pages and the regional health department that covers this area.

Zoning: Most of Granite County has no zoning at all. The county commissioners never adopted a countywide zoning ordinance, so on most raw land you're not fighting a use-zoning fight. The exception: the Georgetown Lake Zoning District and the smaller Denton's Point Zoning District, both created by county commission resolution under Montana's Title 76, Chapter 2 zoning law. If your land is inside either district, you need a zoning permit before you build. Everywhere else, land use is shaped more by subdivision and floodplain rules than by zoning per se.

Dwellings, tiny homes, RVs: The county doesn't have a separate permitting track for tiny homes or single RVs on your own unzoned parcel, mainly because there's no building permit system to plug into. Where it gets regulated is at scale: renting out more than one RV site is treated as a subdivision under state law, and creating new lots (including RV or mobile home parcels) goes through the Granite County Subdivision Regulations via the Planning Department.

Building permits: Here's the big one. Granite County does not run a building permit program, and the county doesn't require permits for residential structures. That's a county-level choice, not a state exemption across the board, commercial buildings and multi-family structures may still need a permit from the State of Montana Building Codes program.

Septic: This is the one permit nobody skips. All new construction needs a septic (OWTS) permit before you build, administered by the Tri-County Environmental Health Department, which covers Deer Lodge, Powell, and Granite counties jointly and applies Montana DEQ Circular 4 standards. Composting toilets aren't specifically addressed in anything I found from Granite County or Tri-County, so I'd call and ask directly before assuming you can skip a septic system entirely.

Greywater and rainwater: I didn't find county-specific rules on either. Absent a Granite County or Tri-County policy, the state DEQ administrative rule baseline should apply for greywater, and DEQ Circular 17 (cistern standards) is referenced for water storage tanks, suggesting rooftop rainwater collection isn't prohibited, but nothing local confirms or forbids it outright.

Wells: No county-specific well ordinance turned up. Well permitting and water rights are a Montana DNRC function statewide, though septic site evaluators do check well-isolation zones as part of their process.

Utilities: With no county building permit program, there's no obvious county mechanism to force a grid or utility hookup. Septic and any applicable floodplain permit still apply no matter your utility status.

Bottom line: verify anything land-specific with Granite County Planning and Tri-County Environmental Health before you buy or build, since so much here runs on "not confirmed" outside the septic requirement.