Pressure gallery, Taschinas power station, Prättigau

New pressure gallery for the new Taschinas hydroelectric power station in Prättigau. Shell construction of the following: Access and pressure galleries; gallery intersection; water reservoir; connecting and pipeline galleries with valve chambers; desanders with gravel and sand drainage galleries including operating room; approach cutting for access galleries with portal construction; approach cutting for pipeline galleries with portal construction.

The pressure galleries are being excavated using a 4.10-metre diameter hard rock gripper tunnel boring machine. The water reservoir (vertical shaft) is being excavated using the raised drill procedure and the remaining excavation is being carried out by conventional blasting.

Map

Specific figures

Order value

CHF 28 million

Construction period

2008 - 2011

Length

3131 m

Total excavated surface

13.2 m2