June 22, 2026 | Mark Luis Foster
We recently blogged about PFAS in Dakota County. Now comes word that Rosemount has some trouble at the ole well.
From South Metro Scoop:
On June 18, Rosemount filled the Steeple Center with water experts from the state health department, the DNR, the pollution control agency, and Dakota County. The big topic — Well #8’s gross alpha radiation — is a natural issue, and experts kept stressing it’s a slow, decades-long risk, not an emergency.
I’m not too pleased to be reading that the whole time I lived in Rosemount (15 years) I was likely ingesting something called gross alpha radiation.
Apparently Well #8 in Rosemount, wherever that is (mostly likely between wells #7 and #9, but I digress) has some issues that are natural causes. So the city held a panel discussion with some experts and the town really showed up. Rosemount, by the way, is home to more than 50 HOAs, according to our ATLAS HOA software mapping.
What they learned:
The health department engineer explained where it comes from: radium and other natural stuff deep in the rock, not anything a factory dumped. He also stressed it’s a “chronic” contaminant, meaning the health risk only shows up after decades of drinking water above the limit — not days or weeks. And Rosemount isn’t alone. Levels jumped across southern and central Minnesota last year because the underground water conditions changed, not because the rules did.
The solutions?
The city’s water engineer walked through the options. They range from cheap and simple to big and expensive: keep Well #8 mostly off, blend it with a nearby well, or build a treatment plant that cleans up several wells at once. That last one would take a couple years to build and several miles of new pipe.
So this particular well does not run often and comes on during hot summer days to keep up with irrigation demands. So perhaps there is no Well #9. They also listed a few helpful FAQs:
Is the water safe to drink right now? The city and the Department of Health both say yes. Gross alpha is a long-term risk measured over decades, and the current level is just over the limit, not wildly above it.
What is gross alpha, in plain terms? It’s natural radiation from radium in the deep rock the city pumps water from. It’s not from a factory, a spill, or the data center.
Why did the level go up? Underground water conditions across southern and central Minnesota shifted last year, pushing levels up in lots of cities — not just Rosemount.
Will my water bill go up? Probably, eventually. The city is still figuring out the cost of each fix. The bigger the fix, the bigger the likely rate impact.
When does the city decide what to do? A final call is expected at the city council in 2026, with construction possibly starting in 2027.
