The Trift Glacier in the central Alps of the Bernese Oberland is an impressive example of the development of a proglacial lake. In 1948, there was still glacial ice at 2,500 metres above sea level. In 2008, a lake had already formed at this site. And in 2014, the glacier ended clearly above the lake. The lake is located on terrain where a dam wall could be built with relatively little effort – the site is therefore considered to be very suitable for a new reservoir. In a participatory process that has been running since 2012, interests with respect to the protection of nature and landscapes have been confronted with those of the electricity sector. Kraftwerke Oberhasli (KWO), an operator of hydropower plants, submitted an application for the construction of a dam wall to the Bernese authorities in 2017.