When Phelps Mill first opened in December 1889, it was powered by one water turbine rather than a water wheel, which is a tall vertical wheel mounted on the outside of a mill. A second turbine was added in 1895 when an addition was built onto the mill. The turbines are located behind the mill in the river. A similar turbine was recovered from the ruins of the Parkdale Mill site twenty miles south of Phelps along the Pomme deTerre River. Water flows into adjustable openings on the sides, strikes a rotor inside that turns the large shaft on top, and exits underneath into the river bottom. The power generated by this turbine was equal to about thirteen horsepower.