Typically hydroelectric stations use either the natural drop of the river or build a dam across the river to raise the water level and provide the drop needed to create the needed force. Water at the higher or upper level goes through the intake into a pipe which carries it to the turbine. The turbine acts like a water wheel that converts the water into mechanical power. The turbine is connected to a generator, and when the turbine is set in motion it causes the generator to move, creating clean electricity. The falling water, having served its purpose, exits the generating station through the draft tube and the tailrace where it rejoins the river.