Off-grid site report

Union County, SD

42.8519, -96.7470 · 1,243 ft elevation

Read this before you act on anything below. This is my researched starting point for Union County, SD, 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 rulesUnion County, SD

Zoning & raw-land occupancy

RestrictedUnion County has countywide zoning in unincorporated areas under its Revised Zoning Regulations, authorized by SDCL Chapter 11-2; incorporated towns have their own separate codes. source

Dwellings, tiny homes & RVs

Unclear - verifySpecific rules on tiny homes or RVs as dwellings were not found in available ordinance excerpts; contact the county Zoning Director for a determination. source

Building permits & codes

RestrictedUnion County Planning & Zoning requires and issues building permits for unincorporated areas using a published application form. source

Septic & composting toilets

Generally allowedSeptic systems follow South Dakota's statewide on-site wastewater rules administered by DANR; no distinct Union County septic ordinance was found, though standard siting setbacks (as illustrated by neighboring Minnehaha County) likely apply. source

Greywater reuse

Unclear - verifyNo Union County or South Dakota state page specifically addresses residential greywater reuse; ask the county Planning & Zoning office or DANR directly.

Rainwater harvesting

Unclear - verifyNo Union County-specific rainwater ordinance was found; state water-rights rules exempt ordinary domestic use below certain thresholds from needing a permit, which likely covers basic household rainwater collection. source

Private wells & water rights

Generally allowedWells statewide, including in Union County, fall under South Dakota DANR's Water Rights Program and must be drilled by a licensed well driller per state construction standards. source

Living disconnected from utilities

Varies locallyNo state or Union County rule bars off-grid living outright, but any structure still must comply with the county's zoning and building permit requirements. source

Open the full county page with sources →

Sun30-year normals

Peak-sun hours, annual average: 4.9 hrs/day
Worst month (sizes an off-grid array): 2.8 hrs/day
Yearly output per 1 kW of panels: 1,422 kWh

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Weather1991-2020

Precipitation: 28 in/yr
Snowfall: 33 in/yr
Heating degree days: 6,698 (cold)
Frost-free season: Apr 30 to Oct 2

How far help isstraight-line

Hospital Sanford Vermillion Medical Center: 10.1 mi
Fire station William J Radigan Fire & EMS Station: 10.3 mi
Hardware store Ace Hardware: 10.4 mi
Grocery Walmart Supercenter: 10.5 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 57010).

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.