Harnessing the River

Harnessing the River. . During the City's early years, a number of industries located at the Falls of the Big Sioux River and used the energy produced by the river's flow to run their machinery. , The Queen Bee Mill and the Sioux Falls Light and Power Company hydro-electric plant are two of the early industries which used the Falls water power. The Mill produced wheat flour and the Light and Power Company generated electricity. The Mill ruins and the power plant building, both listed on the National Register of Historic Places, remain today. Looking up, you can see the historic Mill ruins, a replica of the Mill's turbine house, and historic power plant. , These companies had ambitious plans for their factories and needed a large, reliable flow of water to power their machines. To satisfy this need, the river channel and the rock formations of the Falls were changed significantly by both companies. A dam was built above the Falls to create a mill pond which raised the level of the water. This was necessary to increase the head, or pressure, of the flow and deliver more power to the turbine. At the dam's east end, where you are standing, the water's flow was diverted from the river to spin the turbine. , Capturing the Current , Both the Queen Bee Mill and the Sioux Falls Light and Power Company power plant used the river's flow to power their turbines. Their ways of using the river's power were similar, but there were differences due to the number of turbines (the Mill had one turbine and the power plant had three) and amount of power needed to run the machinery. The Mill's method is illustrated here. , The Turbine House , Inside the Turbine House was the machinery which powered the Mill. The turbine was a large horizontal wheel which turned as water flowed over its angled blades. The turbine, which was attached to the bottom of a long vertical drive shaft, was enclosed in the penstock. , When the gate was open, water rushed through the flume and down the penstock. The pressure of the water forced the turbine to spin, turning the shaft. Above the turbine shaft, a set of gears turned the Mill's main drive shaft. Inside the Mill, a series of gears, pulleys and leather belts powered the machinery. After the rushing water turned the turbine, it exited the Turbine House through the brick arch, spilling into the tail race which channeled the water back to the river. , The Gate House , The mill race funneled water from the mill pond to the Gate House. Inside the Gate House, a wooden gate was raised or lowered to control the flow of water to the turbine. When the Mill was not in use, the gate could be closed to raise the mill pond's water level. When it was time for the machines to run, the gate was raised and water flowed from the pond through an 8-foot diameter iron pipe called a flume to the penstock, which directed the water over the turbine.