Grand Traverse County, MI: EPA's radon zone, explained

EPA's own radon map rates Grand Traverse County zone 3 - low potential, predicting a county-wide average indoor level below 2 pCi/L. Rank it against the rest of the country and Grand Traverse County lands in the 26th percentile for radon potential.

Grand Traverse County by the numbers

Grand Traverse County, Michigan is home to about 96,625 people across 464.336 square miles. Averaged across its land area, Grand Traverse County runs about 208 people per square mile. By population, Grand Traverse County is the 222nd largest of every county sharing its EPA zone — the 79th percentile by population within that zone. EPA's geology-based Region 5 groups Grand Traverse County with 523 other counties nationally sharing its underlying rock and soil profile.

What this actually means for a house in Grand Traverse County

Grand Traverse County's Zone 3 prediction undercuts the roughly 1.3 pCi/L most US homes average, nowhere near EPA's 4 pCi/L threshold for recommending mitigation. A Zone 3 rating means Grand Traverse County's county-wide average is predicted low, but EPA is explicit that a meaningful share of homes in low-potential zones still test above the action level — a low zone is not a reason to skip testing.

Testing and mitigation in Grand Traverse County

For a Grand Traverse County homeowner, the order is simple: test first, since a kit costs a small fraction of what mitigation would. Only if the result clears 4 pCi/L does a system — typically $800–$2,500, about $1,200 for a common install — become worth pricing out.

Find Michigan's state radon program

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

Where Grand Traverse County's figures come from

Grand Traverse County's zone, rank and region all trace back to named EPA and Census sources — the methodology guide lists exactly which ones. Whatever zone Grand Traverse County carries, the zone explainer covers what it does and doesn't tell you about any one house.