Yes, with two things to plan around. The growing season runs about 207 frost-free days. Typical well depths here range from 150 feet to 660 feet, so get a local driller's quote. Flood zones cover parts of the county, so look up any parcel on FEMA's flood map before you offer.
What the land says
Rain
Rain can supply much of a household's water with a large tank. A garden mostly waters itself in normal years.
About 50 inches a year (PRISM, 1991 to 2020 average)
Wells
Well depth varies a lot here. Get a local driller's quote before you offer.
Typical well depths here range from 150 feet to 660 feet
Growing season
A full season for most vegetables.
About 207 frost-free days, USDA zone 7a; last frost about April 6, first about October 31
Sun
Good sun. Size the array and battery bank for winter.
About 4.9 hours of full sun a day, averaged over the year
Flood
Flood zones cover parts of the county. Look up any parcel on FEMA's flood map before you offer.
FEMA maps flood zones in parts of the county
Wildfire
Low wildfire risk.
U.S. Forest Service wildfire hazard map: Very Low to Low here
Storms
Strong tornadoes are common. A storm shelter belongs in the plan.
NOAA: no hurricane-strength storm within 50 miles since 1975; about 5 strong (EF2 or stronger) tornadoes a decade within 25 miles
Earthquakes
Strong shaking is possible. Build to the seismic code and brace the water tank.
USGS seismic hazard map: very high
Terrain
Rolling ground. Look for a flat house site.
Slopes average about 13%, about 480 feet above sea level
Soil
Good ground for a standard septic system. The county's soil test decides.
Silt loam, well drained (USDA soil survey). A standard system typically runs $5,000 to $10,000
Road
Paved roads are close by.
Nearest paved road usually within about 0.7 miles (OpenStreetMap)
Check an Illinois parcel, or plan the one you own
Get a free 0-100 off-grid score.
A step-by-step build plan, sizing your solar, water, garden, septic, heat, and buildings.
Is it legal here?
Zoning
We found no public zoning map for Union County, so call the county planning office with the parcel number to ask whether the land is zoned.
Building code
Illinois does not require counties or cities to adopt a building code, and where a county has none there is no county building permit for a house. Since January 1, 2025, any local code that is adopted must be at least as strong as the International Residential Code on structural design.
Rainwater
Collecting it is allowed.
Composting toilets
Allowed with a permit and an approved unit.
Water rights
Owners of land along a creek or lake can make reasonable use of its water.
Depends on depth, which varies here. Get a driller's quote.
Septic
$5,000 to $10,000
Standard system
Solar and batteries
$18,000 to $34,000
Sized for a modest household
Road or driveway
$3,000 to $8,000
From the nearest road to a house site
Clearing
$1,000 to $4,000
A house site, solar, and garden
Total
$27,000 to $56,000
Before the house, plus the well
Before you make an offer on land here
Well depth
Get a local driller's depth estimate.
Typical well depths here range from 150 feet to 660 feet.
Flood map
Look up the parcel on FEMA's flood map.
Flood zones cover parts of the county. Building in one means flood insurance and extra permits.
Zoning
Call the county planning office with the parcel number.
There is no public zoning map, so we cannot tell whether the land is zoned.
Nearby counties
16,667 people live in Union County, about 40.3 per square mile. It ranks tied for 80th of the 102 Illinois counties we scored, and Illinois ranks 11th of 50 states.