Woodbury County, IA Radon Zone Data

Woodbury County, IA radon potential

EPA places Woodbury County in Zone 1 - Highest Potential — a predicted county-wide average indoor radon level above 4 pCi/L, based on the geology, soil and aerial radioactivity data behind EPA's national map. Nationally that's the 94th percentile for radon potential — Woodbury County outranks 94% of every county EPA has rated.

How Woodbury County compares

Woodbury County, Iowa is home to about 107,257 people across 872.896 square miles. That works out to roughly 123 people per square mile. Within its own EPA zone, Woodbury County is bigger by population than 83% of the counties that share it. Woodbury County falls in EPA Radon Region 7, one of 412 counties nationally EPA assigns to that same geologic province.

What this actually means for a house in Woodbury County

Fixing a home becomes an EPA recommendation past 4 pCi/L, and that is precisely the side of the line Woodbury County's Zone 1 prediction lands on, well above the roughly 1.3 pCi/L most US homes average. EPA's guidance doesn't change because of a Zone 1 label: test the house. What changes is the reason to not put it off in Woodbury County specifically.

Testing and mitigation in Woodbury County

A short-term test kit is the standard first step and typically costs far less than mitigation itself. If a test comes back at or above 4 pCi/L, a radon mitigation system for a typical home runs roughly $800–$2,500 (around $1,200 for a common single-family install), driven mainly by foundation type, not by county.

Find Iowa's state radon program

For Woodbury County, an ongoing number beats a one-time test - a Airthings radon monitor tracks Woodbury County's levels over time. RadonZoneCheck earns a commission there, at no extra cost to you. Use code RADONZONE-10OFF at checkout for 10% off.

Where Woodbury County's figures come from

Every figure on this page traces to EPA's own Map of Radon Zones and Census data, documented in the methodology guide. If you're unsure why a low zone still deserves a test, the zone explainer covers that directly.