The Lake Byllesby Dam was built in 1910 when Henry M. Byllesby & Company constructed it across the Cannon River on the border of Dakota and Goodhue counties. Using mostly hand labor, a crew of 500 to 600 began work in April 1910 and completed the work in just nine months.
The dam created the Lake Byllesby Reservoir, a 3 ½-mile long, 1,432-acre lake.
The concrete dam is more than 1,100-feet long and more than 60-feet high from its base with nearly 400 feet of spillway. The crest of the spillway is 854 feet above sea level.