Off-grid site report
St. Clair County, IL
38.5320, -89.9988 · 551 ft elevationRead this before you act on anything below. This is my researched starting point for St. Clair County, IL, 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 rulesSt. Clair County, IL
Zoning & raw-land occupancy
Varies locallySt. Clair County zoning applies only in unincorporated areas; incorporated municipalities like Belleville or O'Fallon govern themselves. Newly disconnected/annexed land defaults to Agricultural zoning until changed. source
Dwellings, tiny homes & RVs
Varies locallyManufactured homes are permitted with specific width, age, and foundation requirements depending on district; tiny homes and long-term RV residency are not addressed in county sources found. source
Building permits & codes
RestrictedThe county enforces its own Building Code and Property Maintenance Code for unincorporated areas, with permits and inspections required, including for manufactured/modular homes. source
Septic & composting toilets
Generally allowedA permit from the St. Clair County Health Department is required before installing or repairing a private sewage system, per county ordinance layered on state IDPH code; composting toilets aren't separately addressed. source
Greywater reuse
Unclear - verifyNo dedicated county or state greywater-reuse ordinance was found; the county's sewage rules imply wastewater should go to the approved septic system. Ask the Health Department's Environmental Programs division directly. source
Rainwater harvesting
Unclear - verifyNo St. Clair County ordinance addressing residential rainwater catchment was found; confirm with the county Health Department or Building & Zoning before installing a system tied to plumbing.
Private wells & water rights
Generally allowedWells require a St. Clair County Health Department permit under the county's Water Supply Code, which also requires connecting to public water instead of drilling when a public supply is reasonably available nearby.
Living disconnected from utilities
Unclear - verifyNo county ordinance banning electrical grid disconnection was found, but going off-grid for water or sewage still requires the same well and septic permits as any other property.
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
- 1,412 kWh
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Weather1991-2020
- Precipitation
- 42 in/yr
- Snowfall
- 12 in/yr
- Heating degree days
- 4,379 (moderate)
- Frost-free season
- Apr 13 to Oct 15
How far help isstraight-line
- Hospital
SSM Health Cardinal Glennon Children’s Hospital - 14.4 mi
- Fire station
Northwest Scc Fire Department / Northwest Saint Clair County Fire Protection Dis - 2.0 mi
- Hardware store
Don's Hardware - 0.7 mi
- Grocery
ALDI - 0.8 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 62226).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in St. Clair County, IL?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 22, 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.