Off-grid site report
Fremont County, ID
44.5711, -111.3443 · 6,552 ft elevationRead this before you act on anything below. This is my researched starting point for Fremont County, ID, 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 rulesFremont County, ID
Zoning & raw-land occupancy
Varies locallyFremont County has its own countywide Development Code and Planning & Zoning Commission for unincorporated land, but St. Anthony, Ashton, and Island Park each run separate city zoning codes, so it depends heavily on exactly where your parcel sits. source
Dwellings, tiny homes & RVs
Unclear - verifyThe county requires site-plan review and has a building height limit, but specific rules on permanently occupying an RV or tiny home were not confirmed on the county's own site; RVs are treated by the state as vehicles for temporary lodging only, with placement left to local zoning. Ask Fremont County Planning & Building directly. source
Building permits & codes
Generally allowedFremont County requires building permits for unincorporated-area construction and administers the International Building/Residential Code editions as adopted by the State of Idaho; St. Anthony handles its own permits within city limits. source
Septic & composting toilets
Generally allowedSeptic systems are allowed but permitted through Eastern Idaho Public Health, not the county itself, under statewide DEQ wastewater rules; a site evaluation and permit are required before the county will issue a building permit. source
Greywater reuse
RestrictedNo Fremont County-specific greywater ordinance was found; greywater is folded into the same state IDAPA wastewater rules that govern septic, enforced through Idaho DEQ. source
Rainwater harvesting
Unclear - verifyNo ordinance, resolution, or county department page addressing residential rainwater collection was found, so this is not confirmed at the county level; state baseline would apply by default.
Private wells & water rights
Generally allowedThere's no Fremont County water department; private wells and water rights are governed entirely by the Idaho Department of Water Resources under statewide rules, with no added county requirements found. source
Living disconnected from utilities
Unclear - verifyFremont County doesn't have a standalone off-grid ordinance; full utility disconnection is regulated indirectly through building permit conditions, like requiring proof of an approved septic system and site-plan review compliance. source
Sun30-year normals
- Peak-sun hours, annual average
- 4.8 hrs/day
- Worst month (sizes an off-grid array)
- 2.0 hrs/day
- Yearly output per 1 kW of panels
- 1,327 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 26 in/yr
- Snowfall
- 219 in/yr
- Heating degree days
- 9,572 (severe)
How far help isstraight-line
- Hospital
- none within range
- Fire station
Hebgen Basin Fire District Station 1 - 13.2 mi
- Hardware store
Westmart - 13.1 mi
- Grocery
Robins Roost - 3.6 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 83429).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Fremont County, ID?The rules above are the jurisdiction. The land check runs the parcel itself: flood zone, soils and septic suitability, wetlands, slope, access, climate, and these verdicts, from a parcel number or coordinates.
Check a parcel →Share or save this report:New report
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.
New here, or not sure where this fits? Start here walks through the whole thing in order.