Dillon Reservoir Dillon Reservoir Dillon Reservoir, sometimes referred to as Lake Dillon, is a large fresh water reservoir located in Summit County, Colorado, south of I-70 and bordered by the towns of Frisco, Silverthorne, and Dillon. It is a reservoir for the city of Denver, and its waters are under the control of Denver Water. Popular ski areas are close to the reservoir, including Copper Mountain, Keystone, Arapahoe Basin, and Breckenridge. In 1859, a large party of gold-seekers led by Ruben Spalding discovered gold near the headwaters of the Blue River, which prompted a population surge in Summit County, Colorado. By October
US 31–Island Lake Outlet Bridge part of the National Highway System. Island Lake Outlet, also known as the Pine River Channel, was dredged in 1870 to connect Lake Michigan to Lake Charlevoix through Round Lake. A total of five bridges have crossed the channel at this location; the first was a small footbridge built in 1869. The current bridge replaced a swing truss bridge built by the city of Charlevoix in 1901. The US 31–Island Lake Outlet Bridge was designed by the bridge division of the Michigan State Highway Department, led by George M. Foster, and by consulting engineers Haslett and Erdal. Plans were prepared