Off-grid site report

Duchesne County, UT

40.1633, -110.4029 · 5,525 ft elevation

Read this before you act on anything below. This is my researched starting point for Duchesne County, UT, 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 rulesDuchesne County, UT

Zoning & raw-land occupancy

RestrictedDuchesne County has countywide zoning under Title 8 of its code, administered by the Planning Commission and County Commission, so there's no unregulated raw-land living anywhere in the unincorporated county. Minimum lot sizes (often 5 or 10 acres) apply, and some smaller parcels are designated for camping only rather than as buildable dwelling lots, so check the specific parcel's zoning before you buy or move onto it. source

Dwellings, tiny homes & RVs

RestrictedCounty zoning amendments allow an RV as a temporary dwelling only while a permanent home is under construction on the same site, meaning RVs generally aren't allowed as standalone permanent residences. Foundation-built tiny homes fall under the state-adopted IRC like any other house, while tiny homes on wheels are treated as RVs; I did not find a distinct countywide tiny-home ordinance, so confirm specifics with the Duchesne County Planning & Zoning office. source

Building permits & codes

RestrictedDuchesne County requires a building permit for any structure meant for human occupancy, no matter the size, enforced under the state-adopted IBC/IRC by the county Building Official. There's a narrow exemption for a small single-story accessory building (200 square feet or less) once a dwelling already exists on the parcel, but separate electrical, plumbing, and alternative-energy permits can still apply, and new dwellings must also meet the county's Wildland-Urban Interface Code for defensible space and emergency access, enforced by the County Fire Warden. source

Septic & composting toilets

RestrictedTriCounty Health Department is the local authority over onsite wastewater systems under state rule R317-4, and most county lots outside town sewer service rely on septic that must be permitted and approved by TriCounty before a dwelling can be occupied. Not every parcel is guaranteed to support a septic system, since some lots are undersized or have poor soils or high groundwater, and composting toilets aren't specifically addressed in the county materials found, so ask TriCounty Health directly if that's your plan. source

Greywater reuse

Unclear - verifyI couldn't find a Duchesne County-specific greywater ordinance or a TriCounty Health greywater permit page in the research. The state baseline rule (R317-401) likely applies with TriCounty Health Department as the administering authority, but you should confirm directly with TriCounty Health Department before installing a greywater system.

Rainwater harvesting

Unclear - verifyNo county ordinance on rainwater harvesting turned up in this research, so it appears the state rule under Utah Code 73-3-1.5 governs by default with no local modification. If you're planning a rainwater catchment system, it's worth a quick check with the county to be sure nothing local overrides the state rule.

Private wells & water rights

RestrictedPrivate wells in Duchesne County fall under the Utah Division of Water Rights (State Engineer), and the county's own building permit checklist points applicants there rather than to a separate county well ordinance, while also requiring proof of an approved culinary water source for any building permit. Note that the county's R-1 residential district specifically requires connection to public water and a TriCounty wastewater permit, so a private well may not satisfy zoning in that district even if it would elsewhere. source

Living disconnected from utilities

RestrictedFull off-grid living without any hookups isn't really an option for a legal, permitted dwelling here: a certificate of occupancy requires an approved wastewater system in place first, and some zones like R-1 mandate public water rather than allowing a private well. In lower-density agricultural-residential zones a private well plus an approved septic system can likely satisfy the county, but an unpermitted, fully off-the-books dwelling is not authorized anywhere in the county. source

Open the full county page with sources →

Sun30-year normals

Peak-sun hours, annual average: 5.8 hrs/day
Worst month (sizes an off-grid array): 4.3 hrs/day
Yearly output per 1 kW of panels: 1,663 kWh

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Weather1991-2020

Precipitation: 10 in/yr
Snowfall: 31 in/yr
Heating degree days: 7,182 (cold)
Frost-free season: May 14 to Oct 1

How far help isstraight-line

Hospital Uintah Basin Medical Center: 23.6 mi
Fire station Altamont Fire Station: 14.9 mi
Hardware store Kohl's Hardware: 0.1 mi
Grocery Al's Supermarket: 0.2 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 84021).

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 22, 2026; agencies update their layers on their own schedules. Planning data, not a survey or legal advice.