Off-Grid Living in Powder River County, Montana

I'll be upfront: Powder River County, Montana is about as rural as it gets in the Lower 48 (roughly 1,700 people spread over 3,297 square miles), and that shows in how little is nailed down in official records. Broadus is the only incorporated town in the county, and everything outside it is unincorporated land where county control tends to be lighter than what you'd find in a city.

Zoning: I could not confirm that Powder River County has adopted a comprehensive zoning resolution for unincorporated land. The county has a Planning Board and a 2019 Growth Policy, but under Montana law a growth policy is a guiding document, not an enforceable zoning code. Counties in Montana can adopt zoning by resolution, but many low-population rural counties don't bother. Broadus itself may have its own town zoning, separate from the county, but I didn't find that confirmed either. Call the Planning Board to get a straight answer for your specific parcel.

Dwellings, tiny homes, RVs: No county-specific ordinance turned up. The state's IRC Appendix Q (for foundation-built tiny homes) would apply if and where the county has adopted the state building code, and RVs generally fall under state RV and health rules rather than local ones. Again, the Planning Department is your best contact.

Building permits: This is a genuinely open question. Montana law exempts single-family homes from state building-code permitting unless the county has affirmatively opted in, and I couldn't confirm whether Powder River County has done that. Don't guess, call the county.

Septic: This one is solid. Montana DEQ sets the statewide minimum standards for on-site wastewater, and locally the county's Sanitarian / Public Health office handles septic permitting, same model used across Montana counties.

Greywater: No county-specific rule found, so the state DEQ administrative rule governs, in-home reuse (like toilet flushing) is generally allowed without a permit if it runs through a compliant system, while subsurface irrigation use is more restricted.

Rainwater: Nothing at the county or state level prohibits basic rooftop collection for personal, non-potable use, so this looks fine, though large-scale appropriation would fall under DNRC's water rights framework.

Wells: Standard Montana DNRC "exempt well" rules apply (10 acre-feet/year or less, 35 gpm or less, no permit needed, though water right recording still typically applies). The wrinkle here is that Powder River County includes part of DNRC's Powder River Basin Controlled Ground Water Area, tied to coalbed methane development, which can add monitoring or reporting duties. Check with DNRC's Billings Regional Office before you drill. Also note a 2026 rule change requiring a Notice of Intent filing for permit-exception water use from exempt wells.

Off-grid utility disconnection: Not affirmatively confirmed either way. Given the uncertainty around zoning and building-code adoption, going off-grid seems plausible here, but you should confirm septic and any occupancy requirements with the county directly before committing.

Bottom line: Powder River County is genuinely under-documented online, which cuts both ways, it may mean fewer hoops, but it also means you need to call ahead rather than assume.