Key legal question
Which authority is competent to decide a request for water-zins reduction under Art. 50 WRG for a federally granted concession involving international waters?
Extracted holding
The Federal Department, not the cantonal authorities, is competent to decide the reduction request.
Extracted reasoning
For federal concessions, Art. 52 WRG gives the Department the task of fixing the prestations due to each canton. This covers not only Art. 49 WRG but also the water-zins reduction mechanism of Art. 50 WRG, because both provisions concern the amount of water fees and are applied within the same federal-concession framework.