Off-grid site report

Johnson County, KS

38.9938, -94.6534 · 984 ft elevation

Read this before you act on anything below. This is my researched starting point for Johnson County, KS, 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 rulesJohnson County, KS

Zoning & raw-land occupancy

RestrictedJohnson County Planning Department administers countywide Zoning & Subdivision Regulations for unincorporated land, including Rural and Planned Rural districts; the county is currently rewriting these rules. source

Dwellings, tiny homes & RVs

Varies locallyADUs are permitted by right in rural/residential districts under county zoning, and modular homes are defined and permitted with conditions; whether tiny homes on wheels or RVs can be permanent dwellings is not confirmed. source

Building permits & codes

RestrictedThe county adopted the 2018 International Codes with local amendments and requires permits for new dwellings, modular homes, and most accessory structures over a small size threshold. source

Septic & composting toilets

RestrictedJohnson County Community Health Services (JCDHE) requires permits for all onsite wastewater treatment systems, built on KDHE's Bulletin 4-2 state design standards, with an experimental/innovative system pathway for alternatives. source

Greywater reuse

Unclear - verifyNo specific county or state ordinance on standalone greywater reuse was found; it likely falls under the general OWTS/sanitary permitting umbrella. Confirm with JCDHE Environmental Health.

Rainwater harvesting

Unclear - verifyNo Johnson County ordinance addressing rainwater harvesting was found, consistent with but not confirmed against Kansas's generally permissive state approach.

Private wells & water rights

Generally allowedMost residents use public water and wells are uncommon; well construction is governed by state KDHE well construction standards, with no county-specific well ordinance found.

Living disconnected from utilities

RestrictedNo explicit rule requires connecting to public utilities, but building permits require an approved plumbing and wastewater (septic/OWTS) system before occupancy, per the county's adopted building code.

Open the full county page with sources →

Sun30-year normals

Peak-sun hours, annual average: 5.0 hrs/day
Worst month (sizes an off-grid array): 3.5 hrs/day
Yearly output per 1 kW of panels: 1,438 kWh

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Weather1991-2020

Precipitation: 39 in/yr
Snowfall: 13 in/yr
Heating degree days: 4,686 (moderate)
Frost-free season: Apr 5 to Nov 2

How far help isstraight-line

Hospital Cottonwood Springs: 9.7 mi
Fire station Overland Park Fire Department Station 1 - Marty Memorial Station: 1.1 mi
Hardware store Euston Hardware: 1.3 mi
Grocery Natural Grocers: 2.3 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 66208).

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.