Follow the Water: Part 2 - Forebay to Tailrace

Follow the Water: Part 2 - Forebay to Tailrace. The Anatomy of the Pillsbury Waterpower System. , 1882 , Tunnel finished; 2 Victor turbines power the Pillsbury A Mill. Low water levels soon raise concerns about the reliability of waterpower, 1884 , Steam engine installed to supplement waterpower, a move towards less dependence on the Mississippi, 1893 , Steam plant added at 2nd Street and 3rd Avenue SE, 1901 , Downstream Victor turbine replaced with larger, more powerful Samson twin-turbine unit, 1903 , New Main Street steam plant built, followed by a larger steam plant in 1910, further reducing reliance on waterpower, 1955 , Mill stops using waterpower; intake sealed, 1960s , Main Street steam plant demolished, 1992 , Turbines removed, 2003 , Mill produces flour for the last time, 2015 , Pillsbury complex reopens as housing; the waterpower system is reactivated to provide electricity for residents, Forebay, with gates in background (right and left) , Daniel R. Pratt, photographer, 2014, Gates , Jerry Mathiason, photographer, 2015, The mill had two turbines, each with a separate drop shaft. Water entered the mill from the tunnel beneath Main Street through a forebay that directed the flow to the two drop shafts. Water fell 50 feet through the drop shafts to turn the turbines. Each turbine was connected to a vertical shaft that extended up to the basement of the mill and spun a horizontal shaft, which turned leather belts that powered machinery in the mill. After the water passed through the turbine, it went back to the river in a tailrace tunnel that had been bored through solid rock. To stop the turbines, gates in the forebay were closed to keep water from going into the drop shaft., The mill originally had two 55-inch Victor turbines. While they were state-of-the-art in 1881, better designs were soon developed. In 1901, Pillsbury replaced one Victor with a Samson twin-turbine unit. An advertisement by the manufacturer, James Leffel and Company, described the new unit as "of enormous weight and strength." It, too, became obsolete, and was eventually removed. The Pillsbury apartment hydroelectric installation uses only one of the drop shafts and installed a new turbine., "The Pillsbury A Wheel Setting," Northwestern Miller, March 3, 1992, Looking down into drop shaft , Jerry Mathiason, photographer, 2015, Turbine room at bottom of drop shaft, "The Victor Turbine," Northwestern Miller, March 25, 1881, Tailrace tunnel, Tailrace outlet, James Leffel and Company, Pamphlet K of the Latest and Best Types of Samson Turbines, 1902