Off-grid site report

Powell County, MT

46.3502, -112.9798 · 9,971 ft elevation

Read this before you act on anything below. This is my researched starting point for Powell County, MT, not legal advice and not a guarantee. Rules change, and the deciding facts on any specific parcel (setbacks, perc results, overlay districts, deed restrictions, road frontage) live at the county or town office, not in any database. Before you buy land or build, confirm the current rules directly with the local zoning and health offices - the sources on this page tell you exactly who to call.

The local rulesPowell County, MT

Zoning & raw-land occupancy

RestrictedPowell County has adopted countywide Zoning & Development Regulations and a Growth Policy, administered by the Planning Department; this applies to unincorporated county land, not the separately-governed City of Deer Lodge. source

Dwellings, tiny homes & RVs

RestrictedEven small dwellings under 1,500 sq ft have required a Conditional Use Permit before the Planning Board in recorded cases; no separate tiny-home or RV-as-residence ordinance was confirmed, so check with Planning directly. source

Building permits & codes

RestrictedThe county requires a Development Certificate/permit for any new residential structure; whether Powell County or the state Montana Building Codes Program (DLI) enforces structural code is not confirmed and should be asked directly. source

Septic & composting toilets

Generally allowedSeptic (OWTS) permitting is handled by the shared Tri-County Environmental Health office under state DEQ 4 standards; the permit is issued only after the county Development Certificate process, and composting toilets are not addressed in county materials found. source

Greywater reuse

Unclear - verifyNo Powell County-specific greywater rule was found; it appears to default to the state framework, so confirm any local nuance with Tri-County Environmental Health.

Rainwater harvesting

Generally allowedNo county restriction on rooftop rainwater collection was found; cisterns used as part of a private water system fall under state DEQ 17 standards referenced in the Tri-County wastewater regulation. source

Private wells & water rights

Generally allowedWell drilling permits and water sampling are handled by Tri-County Environmental Health, with state DNRC exempt-well rules also applying; Planning Board review has considered well depth and flow when siting new dwellings. source

Living disconnected from utilities

Varies locallyNo explicit grid-connection mandate was found; Planning Board minutes show projects using private wells and on-site creek water approved via Conditional Use Permit, with added fire-safety conditions in Wildland Urban Interface areas. source

Open the full county page with sources →

Sun30-year normals

Peak-sun hours, annual average: 4.5 hrs/day
Worst month (sizes an off-grid array): 2.3 hrs/day
Yearly output per 1 kW of panels: 1,297 kWh

JFMAMJJASOND

Weather1991-2020

Precipitation: 11 in/yr
Heating degree days: 8,751 (severe)

How far help isstraight-line

Hospital Deer Lodge Medical Center: 12.8 mi
Fire station Deer Lodge Fire Department: 12.1 mi
Hardware store Ace Hardware: 12.0 mi
Grocery Safeway: 12.3 mi

From OpenStreetMap. Road miles will be longer, often much longer in hill country.

Plan this spot

These open with this location's real numbers already filled in (ZIP 59722).

Size a solar system Heat loss & insulation Firewood per winter Rainwater harvest Garden size Panel tilt

Sources: US Census Bureau geocoder; NLR PVWatts v8 (solar); NOAA NCEI 1991-2020 climate normals (nearest station) or Open-Meteo (ZIP-centroid) for weather; Open-Elevation; OpenStreetMap contributors. Public data retrieved Aug 21, 2026; agencies update their layers on their own schedules. Planning data, not a survey or legal advice.