Here is a great video about the first underground hyrdroelectric plant ever built. It is located at Snoqualmie Falls in Washington State.
The documenary speaks of FUD about electricity and how a gas company man sabotaged lighbulb demonstrations. It also remembers how cities burned down on a regular basis before electrification.
There is even a image of Nikola Tesla in the intro to the video. The focus is on how the falls were discovered and developed for the electrification of the Northwest.
There are tours available of the facility which still runs with its original equipment.
Trivia: There is a special treat for David Lynch fans if you visit. These falls were featured in the opening credits of the "Twin Peaks" TV series. Snoqualmie Lodge, now called "The Salish", was the front of "The Great Northern" on the TV series. Today it simply a fabulous getaway.