Extension Hieflau HEP - Economical Solutions for the Headrace Tunnel

The expansion project for the Hieflau hydropower plant involves the construction of a second headrace tunnel to enhance the capacity from 60 up to 90 m³/s. The second tunnel, located between the weir system Gstatterboden and storage reservoir Wag, is seen as the highlight of the enhancement scheme. The breakthrough of the 4.9 km long TBM-drive is expected by end of this year.