Every energy source needs to be looked at with a cost-benefit analysis. The materials for wind and solar are not impact-free, and neither is their use. Before we condemn dams, we should compare them to alternative energy sources that would have been used instead (at the time of building), and assess whether the damage is less or more. Dams may be causing the extinction of a few species (which I assume implies they may yet be saved), but we can't assume that an increase in coal or nuclear power would be impact free in overall climate health or the health of individual species (nuclear has a fairly good track record by plant, but statistically having more plants built in the past may have yielded a disaster, and it only takes once to drastically change the averages for nuclear to significantly worse).

The question is, can new dams be built in ways that reduce or eliminate the problems we've encountered so far?