Preservation Work Begins On Dugout Canoe Found At The Bottom of Wisconsin’s Lake Mendota

Photo courtesy of the Wisconsin Historical Society

Wisconsin Historical Society archaeologists, assisted by divers from the Dane County Sheriff’s Office, recovered the historic canoe from Lake Mendota on November 2, 2021

In June 2021, Tamara Thomsen, an underwater archaeologist with the Wisconsin Historical Society, was riding an underwater scooter in Madison, Wisconsin’s Lake Mendota when she spotted what she thought was a log. Upon further investigation, she found it to be a dugout canoe. She took several photos of the vessel and brought them into work to be examined. 

At first, the canoe appeared to have been crafted by a Boy Scout troop from the 1950s. However, Jim Skibo, a Wisconsin state archaeologist, noticed notched stones in the boat that resembled sinkers used by native fishermen’s nets. Because of this, a sliver of the vessel was removed for carbon dating. To their surprise, the canoe was around 1,200 years
old and most likely used by ancestors of the Ho-Chunk tribe or the Effigy Moundbuilders. 

Removing the Canoe 

It took months of planning to get the canoe removed safely from the bottom of the lake, but time was ticking. The sediment that had helped keep the canoe preserved was gone and now that the canoe was exposed, it was at risk of deteriorating.

The Wisconsin Historical Society teamed up with the state’s Native American tribes to execute a plan that safely removed the canoe from the lake. In early November, an archeological team spent three days excavating the canoe and then safely bringing it 27 feet to the surface using inflatable bags. 

As the canoe was carefully brought onshore, people began to cheer. It was an emotional moment. While 37 dugout canoes have been found in Wisconsin, this one is the oldest
and the most in-tact. 

Preservation Efforts 

Now that the dugout canoe has been safely removed from Lake Mendota, the preservation efforts have begun. The efforts will take close to three years to complete. The canoe will be submerged in a tank full of tap water and a bio deterrent to help prevent bacteria from
growing on the vessel. 

From there, a chemical, polyethylene glycol, will slowly be added to the tank to help aid in preservation. Once the polyethylene glycol has settled, the canoe will be removed from the
tank and then freeze-dried. 

Once the canoe is perfectly preserved, it will be ready for display, just in time for the grand opening of the new Wisconsin History Museum in 2026.