Township, Winnebago County, Illinois
Radon Testing in Seward Township, IL
Updated
IEMA does not have enough recorded radon tests in Seward Township to break out separately yet. Winnebago County, Illinois as a whole sits in the EPA's Radon Zone 1, its highest-potential category, so testing is worth doing regardless.
Seward Township sits in the northwest corner of Winnebago County, bordering both Wisconsin and South Beloit, and has been a township since November 6, 1849. It has an estimated 894 residents and 361 housing units across 35.8 square miles.
The ground under Seward Township
Underneath Winnebago County, north-central Illinois, sits Ordovician and Silurian dolomite and limestone, the same bedrock family that runs through much of this part of the state, topped by glacial till from the last Ice Age. The EPA's radon zone map puts the county in Zone 1, its top category for predicted indoor levels.
Housing in Seward Township
Real Census numbers for Seward Township: about 894 residents and 361 housing units spread over 35.8 square miles. At around 25 people per square mile, it's genuinely rural, among the lowest-density places on this site. At this population size the Census Bureau doesn't break out housing age or tenure separately, so what shows up on the Winnebago County towns elsewhere on this site is the nearest real comparison, not a Seward Township-specific number.
Source: U.S. Census Bureau, American Community Survey 2020-2024 5-year estimates (via Census Reporter) and 2024 TIGER/Line county subdivision and place boundaries.
What we do in Seward Township
Radon testing, Buying or selling a home, and New construction.
Common questions
Is radon a problem in Seward Township?
Winnebago County sits in EPA Radon Zone 1, the highest-potential category, so yes, testing is worth doing regardless of the specific house.
We're closing on a house in Seward Township soon. Is there time to test?
Usually yes. A short-term test takes a few days to about a week, which fits inside most inspection periods if it's scheduled early. See our <a href="/real-estate-radon-testing">real estate radon testing</a> page for how that timing works.
Nearby
South Beloit (40.7% of tests at 4+ pCi/L), Rockton (39.2% of tests at 4+ pCi/L), Rockford (36.8% of tests at 4+ pCi/L).
Need radon testing booked in Seward Township?
Tell us why you're testing and any deadline you're working against. You get a fixed price and a straight answer back.