5 Things You Should Know About Minnesota's Wetlands, And Why They Need Us Right Now

Author: Carly Griffith, Water Program Director 

The following was adapted from a conversation with Susan Colvin, stream ecologist and Assistant Professor at Minnesota State University Mankato, and co-author of the American Rivers "Where Rivers Are Born" report.

Minnesota is known as the Land of 10,000 Lakes, but our wetlands may be our greatest environmental asset. They filter pollution from our water, buffer our communities from floods, combat climate change, and provide irreplaceable habitat for birds, fish, and wildlife that make Minnesota, Minnesota.

Right now, these unsung natural heroes are under threat. Proposed federal rollbacks would gut wetland protections to their weakest level since the 1980s. But Minnesota has a chance to step up, strengthen our own protections, and set an example for the rest of the country. We sat down with wetland and stream ecologist Susan Colvin to talk about the hidden benefits of wetlands, what’s at stake in the proposed cuts, and what we can do about it.

For a deeper dive into the wonders of wetlands and what Minnesota can do to protect them, RSVP for our upcoming free webinar  — Protecting Our Wetlands: From National Cuts to Minnesota’s Moment. 

1. Wetlands Are All Around Us

Minnesota’s wetlands include the marshes, swamps, peatlands, and prairie potholes most of us picture — with swaying cattails and tall reeds — but they also encompass something less visible: the small streams and waterways that quietly feed and connect our lakes, rivers, and groundwater. Ephemeral streams flow only after rain. Intermittent streams flow seasonally. Together with isolated wetlands like prairie potholes, these smaller, lesser-known systems form the connective tissue of Minnesota’s water landscape.

“Headwater streams make up the majority of our watersheds,” says Sue. “They contribute most of the flow to our bigger downstream systems.” That means the health of the Mississippi, the Minnesota River, and every lake you fish or swim in is connected to the health of these easily overlooked ecosystems.

Minnesota’s prairie potholes are especially unique. They were created from our state’s glacial history, are found almost nowhere else on earth, and are critical for preventing flooding and providing habitat for migratory birds. We’ve lost most of them, making the ones that remain even more critical. 

2. Wetlands Benefit Our Water, Climate, and Communities Every Day

Wetlands are among the most effective water filtration systems on the planet. The process they use to break down nitrates and remove contaminants, including PFAS, is something we simply don’t have the technology to reproduce at scale. No treatment plant can do what a healthy wetland does naturally.

But filtration is just the beginning. Wetlands absorb excess water, protecting homes, infrastructure, and farmland from flooding, and our pocketbooks from flood losses. They’re also Minnesota’s most powerful natural defense against climate change: our six to seven million acres of peatlands store the equivalent of 27 years of our total annual greenhouse gas emissions beneath their mossy surface. And they’re essential habitat for a wide array of plants and animals — some found nowhere else — from wild rice and blue herons to salmon, trout, and the great gray owl.

There’s an economic dimension too. In Minnesota, a home on a lake is worth about $200,000 more than an inland home, and data shows property values climb for every centimeter of water clarity.

With so much tied to the health of our wetlands, Minnesota cannot afford to let them degrade.

3. The Federal Rollbacks And What They Could Mean for Wetlands and Water Across the Country

Proposed changes to federal wetland rules threaten to weaken national protections to their lowest point since the 1980s. Unless states step in to fill the gaps, the loss could be devastating.

“In the U.S., we could lose protections for wetlands that cover an area the size of the state of West Virginia,” Colvin said. “If that becomes a reality, it will result in a lot of dirty water going into our permanent river systems, and a lot less recharge of our groundwater aquifers that supply drinking water.”

The most direct cuts would fall on the ephemeral and intermittent streams mentioned above that serve as the critical links between headwater systems and the lakes and rivers we depend on. Prairie potholes would also lose federal protection. Under a recent Supreme Court decision, wetlands must have a continuous surface connection to navigable waters to qualify for federal protection. That’s a standard that prairie potholes, which sit outside floodplains, have never met. That means the wetlands most essential to curbing nitrate pollution and storing excess water in the Minnesota River Basin would be left vulnerable, increasing the risk of flooding for downstream communities.

The problem is only compounding: many streams that once flowed year-round have become seasonal in recent years due to climate change and increased groundwater withdrawals, meaning protections that already fall short would cover even less than they do now. 

The indirect damage, however, could be even greater.

“It’s like trying to protect the blood in our body by only protecting the primary veins and arteries around our heart,” Colvin said. “The whole body cannot function in a healthy way without those other veins and capillaries that deliver blood to the rest of our body.”

4. Consequences of wetland loss in Minnesota

Minnesota has already lost 50 percent of its original wetlands, and 95 percent in the state’s western and southern regions. Most were drained to make way for agricultural expansion, a practice that continues today under state drainage laws that are more than 100 years old and were never written with wetland protection in mind.

The consequences are real and growing. Without wetlands like prairie potholes to filter and absorb excess water, our rivers — particularly the Minnesota River — are more volatile, leading to impaired water quality, more intense flooding, and erosion that threatens homes, roads, and other infrastructure.

The 2024 collapse of the Rapidan Dam in southern Minnesota is a stark example of the kind of catastrophic event that becomes more likely as we continue to lose the natural water storage that prairie potholes provide. A warming climate only compounds the risk, as intense rain events become more frequent across the region.

That’s why MCEA has been fighting on multiple fronts. In addition to advocating for stronger state wetland protections, MCEA authored a report on drainage last July and recently filed a lawsuit seeking to reform drainage practices to better protect our water, communities, and natural resources.

5. Minnesota’s Moment to Lead

Later this spring, Minnesota is expected to open a public comment period on its wetland rules for the first time in nearly two decades. This is our moment to act. If we seize it, Minnesota can not only fill the gaps left by federal rollbacks, keeping our own wetlands healthy, but also set an example for the rest of the country.

Minnesota must ensure protections extend to headwater streams and isolated wetlands alike, including the prairie potholes of southern and central Minnesota that are most at risk and most needed. We also need better balance between agricultural considerations and the water and wetland protections that benefit all of us.

What happens here matters beyond our borders. Minnesota is one of the nation’s leading wetland states, trailing only Alaska and Florida in total wetland acreage. 

“It is common for states to lead the way on solving environmental problems. States, including Minnesota, regulated PFAS before the federal government,” Colvin said. “As the federal government is poised to lessen protections that will dirty our water and set off a cascade of consequences, this is Minnesota’s opportunity to showcase our ability to lead again. It is not unreasonable to think we will come up with solutions that solve problems elsewhere.”

Register for MCEA’s free upcoming webinar — Protecting Our Wetlands: From National Threat to Minnesota’s Moment — to learn more and find out how you can make your voice heard when the comment period opens.