Off-grid site report

Silver Bow County, MT

46.0034, -112.6636 · 5,338 ft elevation

Read this before you act on anything below. This is my researched starting point for Silver Bow 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 rulesSilver Bow County, MT

Zoning & raw-land occupancy

RestrictedButte-Silver Bow has adopted unified zoning (Title 17) covering the whole consolidated city-county, unlike many Montana counties with no zoning. The ordinance is under a full rewrite, so confirm current district rules with Planning. source

Dwellings, tiny homes & RVs

Unclear - verifyThe county enforces the 2021 IRC for standard construction, but no county-specific rule on tiny homes on wheels or long-term RV occupancy was found; this likely falls under Title 17 use/occupancy provisions once finalized. Confirm with Planning or Building & Code Enforcement. source

Building permits & codes

RestrictedButte-Silver Bow has opted into full local building code jurisdiction, requiring permits and enforcing the 2021 IRC/IBC and related codes for residential, mechanical, and plumbing work, stricter than the state's default exemption in some counties. source

Septic & composting toilets

Generally allowedThe Butte-Silver Bow Environmental Health Division requires a local permit for any structure with onsite wastewater disposal, enforcing state DEQ Circular 4 and ARM standards. Composting toilets as a stand-alone system are not confirmed; ask Environmental Health. source

Greywater reuse

Unclear - verifyNo Butte-Silver Bow ordinance specifically addressing greywater reuse was found; likely defers to the state ARM baseline. Confirm with the Environmental Health Division. source

Rainwater harvesting

Unclear - verifyNo county-level rule on rooftop rainwater collection was found; the state baseline (no prohibition) likely applies, but this is not locally confirmed.

Private wells & water rights

RestrictedSilver Bow County contains a state-designated Controlled Groundwater Area where new groundwater appropriations must be approved by the Butte-Silver Bow Board of Health/Water Quality District, stricter than the standard DNRC exempt-well process used elsewhere in the state. source

Living disconnected from utilities

RestrictedNo explicit rule forces grid connection, but mandatory building, septic, and (in some areas) well permitting means any legal dwelling must still meet code-based water and sewage systems even off-grid. source

Open the full county page with sources →

Sun30-year normals

Peak-sun hours, annual average: 4.8 hrs/day
Worst month (sizes an off-grid array): 2.6 hrs/day
Yearly output per 1 kW of panels: 1,370 kWh

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Weather1991-2020

Precipitation: 13 in/yr
Snowfall: 62 in/yr
Heating degree days: 9,220 (severe)

How far help isstraight-line

Hospital Saint James Hospital: 5.7 mi
Fire station Boulevard Fire Department: 5.8 mi
Hardware store True Value: 6.8 mi
Grocery Dancing Rainbow Natural Grocery: 6.0 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 59748).

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.