Electricity from Water

This is not exactly something that most people can use in their homes, unless they have a flowing stream in theri backyards but I wonder if an older application for producing energy might work on a micro scale, say for a municipality in North America or a village in the developing world, namely the power of moving water. One of the very first sources of power for doing work was the power of moving water. From the Middle Ages of Europe to the Sung Dynasty of China to the British colonies in America water driven wheels created mechanical energy to grind grain and saw wood. Later, with the development of the turbine the same mechanism, moving water, generated electricity. Once constructed, small, water driven turbines could generate electrical power at minimal cost. Streams with slower currents could be channeled into narrow, fast flowing currents with dams (with fish ladders to enable andromodous fish to spawn). Many settlements from major cities to tiny villages are located close enough to a body of water for this to be considered. Also consider the power of ocean waves. The sea is constantly in motion. Could tidal movement not be harnassed to power turbines ? The wind does not always blow but tidal movement is a constant and once generated tidal driven electrical energy could be transmitted by wire hundreds of miles inland.. Maybe communities need to take a closer look at nearby bodies of water to see if they are suitable for such construction.