In the late 20th century, and probably throughout the 21st century and beyond, water power still has a place in America. Today, instead of generating mechanical energy to be used on-site, the energy of falling water is frequently converted to electrical energy to be transmitted for use elsewhere.

The turbine is a carefully engineered and highly efficient means of harnessing water power. Water is smoothly funneled into a restricted space where it turns the precisely designed impeller blades of the turbine, much as a breeze turns an unplugged electric fan. On the same axle as the turbine is a compact gear box and electrical generator. After the turbine has extracted most of the water's energy, the water flows gently downstream; very little energy is wasted by turbulence.