The decision recently to shut down additional wells in Eau Claire due to PFAS contamination is concerning. It’s also good news in some ways.

The decision brings the total number of wells shut down to seven. Eau Claire draws water from a total of 16 wells. The city, officials have said, has plenty of water to supply the community’s 9 million gallon per day demand.

Concerns about contamination are warranted. PFAS chemicals are sometimes called “forever chemicals.” The United State Environmental Protection Agency says the chemicals have been used since the mid-20th century, and they’re “very persistent.” Unlike most chemicals, these don’t break down and they can build up in people or animals. The concern is that they may cause health problems, though studies to determine just what levels and effects they have are ongoing.

In short, they probably aren’t something you want in your glass of water.

Officials suspect the contamination came from firefighting foam used at the airport. It’s not certain, but it seems to be the direction city and federal officials are leaning in. Any remediation steps will depend on the final conclusions.

It’s impossible to overstate the importance of this issue. Water is central to the fundamental ability of humans to exist together in significant numbers. It’s why the plains states went without major settlements for much of the nation’s westward expansion. Tribes knew where the water was, but settlers didn’t. In the 19th century the plains were called “the Great American Desert.”

Take things back further. The Roman mastery of engineering and construction is displayed in aqueducts that still stand some 2,000 years after they were constructed. Water was so crucial the society developed sophisticated calculations and techniques to transport it for hundreds of miles. That’s how important water was, and is, to human society.

So how is this good news? Well, for one, we know the chemicals are there.

This isn’t a situation in which some contaminant has crept into the wells while we’re not looking, nor is it a situation in which we don’t even know to test for this particular set of chemicals. The testing found the contamination, and ongoing testing was able to spot a spread in the chemicals.

Eau Claire is also able to take active steps. To keep that spread from infecting additional wells, the city is pumping three of the previously-shuttered wells into holding lagoons. It seems to be working; tests showed levels dropping in early October.

There doesn’t appear to be any imminent risk to the city’s supply as a whole, either. As long as five wells remain operational, officials say they can continue to cover the city’s needs. Lane Berg, the city’s utilities manager, said Eau Claire has “a lot of redundancy” in its water supply system.

State officials agree. Matt Thompson, a Wisconsin DNR hydrogeologist, backed the steps Eau Claire is taking to ensure safe water. He said the testing will continue to ensure safe drinking water for residents.

And that’s the most important thing. Yes, vigilance is required. But this is a known problem with a known response. Eau Claire doesn’t have to make things up as it goes along.

This story isn’t over, not by a long shot. Monitoring will have to continue. Remediation measures that go beyond what the city is currently doing may eventually be required. And we don’t blame people for being a bit concerned by it all.

But you can’t deal with what you don’t know. It’s unfortunate that we’re now having to deal with PFAS contamination, but we’d far rather know to take protective steps than not know the problem exists.