If we factor in all the now common annual flood damage, in perpetuity, and potential loss of life from lack of reservoirs for water to fight fires, and the continual rebuilding of levees, bridges (such as the one now needing to be built to replace the one on 101 ($18 - 25 million, plus inevitable over-runs), why, yes, I think it would have been cheaper to leave them in place, perhaps boring under them to drain the lakes in flood season and installing a gate valve to restore their storage capacity in summer. It's all a moot question, of course, but the feds are now talking about removing more dams and I hope they consider all the consequences, especially in Eastern WA, where the effects of drought in a time of global climate change may well be more costly.