This is a technical problem with technical solutions. You can just fix things, you don't need to throw out 30% of your power generation to pay billions for climate change vagueposting.
Restoring river water levels can't be done through technical solutions though, they rely on the weather and we can't control that. The European river levels are largely influenced by inland rain, snowfall, and glacier forming/melting; snowfall and rain has been meagre this year, glaciers have been melting and receding for decades now.