Facts
The foundation Trägerstiftung Kultur- und Kongresszentrum am See (appellant) had received a building permit in 1994 for the construction of the Culture and Congress Centre Lucerne (KKL). The roof of the KKL is covered with copper sheeting and has an area of around 9'400 m². The rainwater is discharged into Lake Lucerne.
In 2006, the Office for the Environment and Energy (uwe) found that the roof water was to be qualified as polluted wastewater and obliged the appellant to conduct a feasibility study to reduce copper runoff.
The appellant appealed to the Administrative Court of the Canton of Lucerne and requested that the decision be revoked and the procedure for reducing copper runoff be discontinued. The Administrative Court dismissed the appeal.
The appellant filed an appeal in public law matters with the Federal Court and requested that the judgment of the Administrative Court and the decision of the Office uwe be revoked and the procedure regarding the reduction of copper runoff be discontinued.
Considerations
The Federal Court examined whether the roof water of the KKL was to be qualified as polluted wastewater. It found that the water protection legislation prohibits any pollution in the sense of Art. 4 lit. d WPA and that the authorities must consider both the relevant emissions of the wastewater and the immissions at the point of discharge when making…