About Zillergrund Dam

The Zillergrund Reservoir in the Zillertal Alps of Tyrol was completed in 1986 and works in close hydrological partnership with the neighbouring Zillergründl reservoir. The 186-metre arch dam impounds 85 million cubic metres from the upper Ziller River tributaries. Together the two Ziller reservoirs form a pump-storage system where water can be transferred between basins to optimise electricity generation against demand. The Zillertal valley is one of Austria's most visited alpine destinations, and the reservoir lies within hiking distance of several high-altitude refuges. The dam's construction coincided with the major expansion of Austria's hydroelectric capacity in the 1980s, a decade that saw significant investment in pumped storage to balance the emerging nuclear phase-out policy. The Ziller catchment's high snowfall and glacial cover ensure reliable annual inflows, though climate projections indicate a gradual reduction in glacier-derived water over the coming decades. The reservoir supports important Alpine ecosystem services, including habitat for the Alpine ibex population reintroduced to the Zillertaler Alps in the twentieth century.