From what I've read about this issue is that the 4 lower Snake River Dams should be breeched to restore the river to it's natural state. This would remove the 300 miles of lakes behind the dams.
The dams generate a little power and provide some irrigation but their major purpose is to create a seaport at Lewiston Idaho. The problem is not so much adult fish returning up river but juvinile smolt trying to migrate down river. Up river from Lewiston there are thousands of miles of spawning and rearing habibtat in pristine condition, but nobody's home.
Removing the earthen section of the dams would leave the concrete structures in place, mothball the power generators and leave the locks in place. They could easily be put back in use if needed later or if this action did not restore the fish. Studies indicate that the cost of removing the earthen structures would cost less then what we now spend on maintaining the dams.
It's a very emotional and volitale issue here in Idaho. The U.s Fish and Wildlife Service shoved Wolf Reintroduction up our butts and I moan and groan, Why didn't they choose Salmon instead.