removal of hydro-electric dams

The world needs to start using more renewable energy sources but is hydro electric dams the way to do it? By using hydro electric dams it effects the natural flow of the rivers and it doesn't allow migrating fish such as salmon to migrate back to their spawning grounds.
My favorite documentary of all time 180° south examines the troubles going on in patagonia as there proposing building dams in the last true frontier. This issue still exist today because it is a true moral dilemma. Do we solve the century long dilemma of making green energy or do we destroy natural beauty to put in a massive concrete wall in the middle of one of the most beautiful untouched areas in the world.
By building these dams government officials are forced to spend billions of dollars on finding ways to keep endangered salmon alive and that is usually through hatcheries and that cost money. so instead of spending billions on try to fix a problem why not just get rid of what caused the problem.
There are plenty of other ways to create green energy that does not effect the environment nearly as much as hydro does so why not save the pristine rivers and natural beauty and just build solar fields in the middle of the desert where no one will ever see them.

http://www.patagonia.com/new-localism/damnation.html