The Giant Floating Island of Lake Chippewa Has to Be Pushed by Boats Almost Every Year

Wisconsin’s Lake Chippewa is home to a giant floating island that sometimes moves around blocking a critically important bridge and needs to be moved by local boat owners working in unison.

Lake Chippewa, aka the Chippewa Flowage, was created in 1923, by flooding a large swamp. Soon after that, many of the peat bogs started rising to the surface and became perfect growing spots for plant seeds carried by wind and wild birds. As the years passed, plants from grasses to trees began to grow and their roots actually caused these floating bogs to grow. Today, they vary from the size of a parking space to several acres, with the largest of them, the so-called “Forty Acre Bog” on the west side of the lake featuring mature trees. Almost every year, dozens of local boat owners team up to push it away from a bridge connecting the East and West sides of the lake.

Photo: AirFox Photography

“It’s almost every year. It takes a community effort and you have to have the winds at your back in order to push them in,” one local man told Northern News Now.

According to the Chippewa Flowage website, the lake’s unique floating islands start out as mud flats risen from the swamp at the bottom, but as time goes by, vegetation starts to grow, and the oldest islands even have trees that act as sails when the wind blows, moving the entire floating mass around the lake.

Photo: John Buvala

“It’s one of the first things you look for when you come in here in the morning: Where’s the bog?” local man Denny Reyes said.

The decades-old floating island doesn’t move around all the time, but when it does, it can cause headaches for the locals by blocking an important bridge which happens to be the only passage between the East and West sides of the lake. When that happens, the only way to move it is by boat. And not just one big boat, but dozens of them working in unison, with the wind at their back. Last year, 25 boats were used to push the floating island away from the bridge.


When we move it, we gotta get it kind of in the right spot, or it can be back in in a couple of days, local homeowner Greg Kopke said.

Because floating islands like the Forty Acre Bog are a habitat for various animal species, they are protected by law and cannot be broken apart.