Safeguarding Our Wetlands

Wisconsin’s wetlands are vital to the health and vibrancy of our waters.

Wetlands purify our water, sequester climate-changing carbon, protect our homes from flooding, and support the life of diverse and rare wildlife. They also provide limitless value and enjoyment for bird waters, anglers, kayakers and paddlers, and many others.

Wetlands in Wisconsin have long been a threatened resources. According to the Wisconsin DNR, half as many wetlands remain today as in the 1800s. And in our own time, the threats continue.

What are Wetlands?

Wetlands are transition zones between land and aquatic systems. It’s the place where water flow, nutrients, and the sun’s energy meet to create an ecosystem distinguished by hydrology, soils, and vegetation. Wetlands are not only vital in providing habitats for thousands of species, they are also critical in absorbing excess floodwater and improving water quality. 

Types of wetlands

Big & Little Marsh Wisconsin State Natural Area #391 Door County

Marshes

Marshes are wetlands that are flooded permanently or during high water periods. Located near the edges of ponds, lakes, rivers, and streams, marshes are characterized by plants either submersed, floating-level, or emerging vegetation. Marshes can be witnessed throughout Wisconsin, and often are home to cattails, pondweeds, and waterlilies.

Milwaukee River & Swamp Wisconsin State Natural Area #93 Fond du Lac County

Swamps

Swamps are nutrient-rich wetlands where woody vegetation is prevalent and typically have standing water during the “least certain times of the year.” Northern white cedar, American elms, ferns, sedges, grasses, and flowering plants can all be found in swamps.

Dorys Bog and Hunt Hill Natural Area

Bogs

Bogs are nutrient-poor basin wetlands in which rain is their only source of water, as bogs aren’t typically fed by surfacing groundwater or streams. Due to its acidic environment, bogs are home to many unique carnivorous plants, such as sundews and pitcher plants, as well as “economically important species” such as blueberries and cranberries.

Namekagon Fen Wisconsin State Natural Area #476 Bayfield County

Fens

Fens, the rarest type of wetland in Wisconsin, are fed by mineral-rich groundwater and seep water out of the soil’s surface. Characterized by its low growing plant community, active springs, and trout streams of cold, clear water, fens disproportionately provide a home for endangered, threatened, and rare species.

Latest News

| As Seen in the Defender

Understanding the impact of neonicotinoid insecticides on agriculture and the environment

| As Seen in the Defender

Saluting Senator Rob Cowles, Environmental Champion

| As Seen in the Defender

Wisconsinisms: Good for Old Fashioneds, bad for your energy bills

| As Seen in the Defender

Rural champions for solar

| As Seen in the Defender

Under the Lens: Launching the Environmental Health Initiative

| As Seen in the Defender

The old and the new

| As Seen in the Defender

IRA at the Black Business Hub: Celebrating the second anniversary of the Inflation Reduction Act

Join Clean Wisconsin's

Action Network

We’ll send you regular updates with opportunities to make your voice heard and help protect Wisconsin’s environment.

Join thousands of our members and supporters across the state who share our vision of plentiful clean water, breathable air, and clean energy. Your membership gift strengthens our voice in the capitol, in the courts, and with decision-makers.

Why are wetlands important?

Wetlands naturally improve water quality – they absorb excess nutrients, sediments, and pollutants before they reach larger bodies of water. Wetlands are often described as the environment’s kidneys, filtering out nitrates, phosphorous, and heavy metals. Wetlands are essential in maintaining clean and plentiful drinking water.

Wetlands are a critical tool to controlling floods. They act as a natural sponge, absorbing and holding excess water from rainfall, and slowly releasing it into surrounding environment.

Climate change has caused an uptick in unprecedented storms, like we have seen around Wisconsin in recent years. As we lose wetlands, rivers and lakes must be more accepting of rainfall. With that, we lose water quality and risk increased flooding.

As we are experiencing the deadly consequences of climate change, we need to remember that wetlands are crucial in mitigating the effects of climate change. Wetlands cover 5 to 8% of the earth, but hold upwards of 30% of soil carbon.

According to the Wisconsin DNR, 32% of the state’s species depend on wetlands for living and breeding, including a disproportionate amount of endangered and threatened species such as the Piping Plover and the Whooping Crane. Disturbances in the wetland’s ecological systems open them up to invasion by non-native invasive species, such as Zebra Mussels.

Rush Lake Wisconsin State Natural Area #331 Winnebago CountyA Disappearing Resource

Wisconsin originally had 10 million acres of wetlands. The state has since lost 47% of wetlands, with the remaining 5.3 million located mostly in the northern third of the state, according to DNR. In southern Wisconsin, wetland loss is upwards of 75%.