Look a little closer, it is not. (grass growing in the bed, fisherys depend on this) Nice uneven riverbed. Lots of people fish the South fork. The Yuba river below Bullards Bar damn on the other hand looks a lot like the LA river, flat bottom, no plants, few fish, banks undermined. (sorry no pictures on hand, but I've been there)
Sure nature scoures the river, damns do it with less fury but much higher frequency.
My point all along is that power is only one of the purposes of a dam, others are recreation, flood control and irrigation. Each of these other activitys has economic value. Dam operators have to balance each of these while remembering that they are all subject to diminishing returns.
You are correct. It is not "lifeless" . . . nor is it any more or less "verdant" than the areas in question.
Prior the hydro development of the American river canyon the "fisheries" of the lower stretches of the river(that part in question) consisted of carp, small mouth bass, frogs and crayfish. The summer water temperature was too warm for trout.
Today the water temperature is too cold for bass and most carp. TROUT LOVE IT! The ecology of the river has already adapted.
There is no substantial ecological/environmental argument to float this bill.
Uh . . . excuse me . . . there IS an argument - one that is contorted and bogus.