This pump, designed by Edwin Reynolds (1831-1909) and built by the Edward P. Allis company, is the major component of one of the earliest water-pollution control systems. It was capable of pumping more than a half billion gallons of water a day, the highest-capacity pump in the world when installed. It still is used during the summer to pump water from Lake Michigan into the Milwaukee River upstream of the downtown area. This maintains a current in the lower portion of the river and greatly reduces the concentration of pollutants.
The Mackinac (pronounced "Mack-in-awe") Bridge (1957) spans the Straits of Mackinac between Lake Michigan and Lake Huron, connecting the Lower and Upper peninsulas of Michigan. Prior to the construction of the bridge, a fleet of nine ferries would carry as many as 9,000 vehicles per day, with traffic backups stretching as long as 16 miles.