Off-grid site report

Mahaska County, IA

41.2970, -92.6686 · 820 ft elevation

Read this before you act on anything below. This is my researched starting point for Mahaska County, IA, 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 rulesMahaska County, IA

Zoning & raw-land occupancy

Unclear - verifyMahaska County has subdivision plat/plan regulations under Iowa Code Chapter 335, but no public zoning ordinance page (districts, lot sizes, permitted uses) was found. Whether raw land occupancy is restricted is not confirmed; ask the Board of Supervisors. source

Dwellings, tiny homes & RVs

Unclear - verifyNo county-specific rule on tiny homes, manufactured homes, or RVs was found. Falls back to the state baseline under Iowa Code §335.30 limiting extra county restrictions on HUD-code manufactured homes on ag land.

Building permits & codes

Unclear - verifyNo Mahaska County building-permit office or code adoption page was found; not confirmed whether the state building code applies to unincorporated areas. Incorporated towns like Oskaloosa set their own separate building rules, not researched here. source

Septic & composting toilets

Generally allowedMahaska County Environmental Services, run by a County Sanitarian, issues septic permits and licenses septic contractors, under statewide Iowa DNR rules (567 IAC Ch. 69) that delegate enforcement to counties. source

Greywater reuse

Unclear - verifyNo Mahaska County or Iowa DNR page specifically addresses greywater reuse. Ask the county Sanitarian before installing a system.

Rainwater harvesting

Unclear - verifyNo Mahaska County or Iowa DNR rule permitting, restricting, or prohibiting rainwater catchment was found; treat as unconfirmed.

Private wells & water rights

Generally allowedMahaska County Environmental Services issues construction permits for private wells serving under 25 people or 15 connections, per Iowa DNR rule, and requires a DNR-certified well contractor on site. source

Living disconnected from utilities

Varies locallyNo ordinance requiring grid utility connection was found; the practical requirements are the septic and well permits through the county Sanitarian's office rather than a direct on-grid mandate. 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): 3.5 hrs/day
Yearly output per 1 kW of panels: 1,424 kWh

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Weather1991-2020

Precipitation: 38 in/yr
Snowfall: 25 in/yr
Heating degree days: 6,623 (cold)
Frost-free season: Apr 24 to Oct 8

How far help isstraight-line

Hospital Mahaska Health Partnership: 2.0 mi
Fire station Oskaloosa Fire Department: 1.3 mi
Hardware store Malcom Lumber: 0.3 mi
Grocery Walmart Supercenter: 0.1 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 52577).

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.