water and electrical infrastructure

in Moccasin, California last summer.  Moccasin has a hydroelectric power plant that provides electricity for San Francisco (and the rest of the Northern California region via the overall power grid) as a part of the Hetch Hetchy Water and Power utility that the City and County of San Francisco owns.

Here is a view of Moccasin's reservoir: 

The water leaves the hydroelectric plant to the right of the picture and travels under the mountain to the left, eventually making it to the sinks, showers, and lawn sprinklers of San Francisco.