Going forward, so long as you have competent engineering, the biggest risk of hydro power will be your water sources effectively drying up. (That could be literal, or diversion to irrigation and other uses, or various combinations.)

But the yet-bigger problem with hydro power is the extreme scarcity of suitable dam locations.

Competent engineering isn't enough. You also need to never end up being in a war zone, and being able to commit to ongoing maintenance forever, or outlawing all construction far downstream (or finding the even more scarce type of locations where nobody wants to build downstream).