Archaeologists have recovered a 1,200-year-old dugout canoe from the depths of Lake Mendota in southern Wisconsin. The canoe was first spotted in June by Wisconsin Historical Society maritime archaeologists Tamara Thomsen and Mallory Dragt. Thomsen took a closer look at what appeared to be a piece of a log embedded in the lake bottom and realized it was a dugout canoe.
The wood was in such good condition that archaeologists questioned how ancient it could be, but the presence of net sinkers — notched stones flattened by hand tooling used as weights on the ends of fishing nets — strongly suggested it predated the arrival of Europeans. It was on a slope 27 feet below the surface, which had preserved it in relatively cool, dark waters until it was recently exposed by the shifting deposits of the lake bottom. No longer protected by its environment, the canoe had to be recovered quickly before it began to deteriorate.
A careful operation to excavate and recover the full canoe began in October. Last week, divers from the Dane County Sheriff’s Office working with the Wisconsin Historical Society dredged out a trench around the canoe to liberate the boat. Rebar was wedged underneath it to support it. It was slowly raised to the surface by flotation bags. Boats then towed it and the four 45-pound sandbags weighing it down to shore at snail’s pace of 1.1 miles per hour.
A sample from the canoe was radiocarbon dated to around 800 A.D., making it one of the oldest intact water vessel ever discovered in Wisconsin. It was carved during the Effigy Mound Period when the indigenous people of the area built animal-shaped mounds around Lake Mendota.
The canoe is now at the State Archive Preservation Facility where it is bathing comfortably in a custom-built vat of bio-deterrent solution that will kill any algae or microbes that would accelerate the decomposition of the wood once exposed to the air. After that stage is complete, the canoe will be soaked in polyethylene glycol. PEG replaces the water in the wood with a waxy substance which will prevent drying and cracking.
“The dugout canoe found in Lake Mendota is a significant artifact of the continuum of canoe culture in the Western Great Lakes region,” said Christian Overland, the Ruth and Hartley Barker Director & CEO for the Wisconsin Historical Society. “By taking action to preserve this canoe we are protecting a piece of history for future generations. The canoe is a remarkable artifact, made from a single tree, that connects us to the people living in this region 1,200 years ago.”
The stabilization process is expected to take three years. Once it is complete, the dugout canoe will go on display at the Wisconsin Historical Society’s new museum in Madison, currently scheduled to open in 2026.