Pumped storage hydropower plant Linth-Limmern

Baden, Switzerland

Los A2, hydroelectric power stations.


The 'Linthal 2015' project is intended to increase the capacity of the Linth Limmern hydroelectric power station. Hydro-energy production to be increased from 480 MW to 1,480 MW. For this purpose, impressive underground structures were constructed in the midst of the Alps, between 1,500 and 2,500 metres above sea level: over 4 km of tunnels with an excavation volume of approx. 550'000 m3, two pressure shafts, a surge chamber, a turbine cavern and a transformer cavern with a ridge height of more than 50 m and containing 4 machine groups. Under demanding climatic conditions, difficult access and extremely difficult logistical and environmental conditions, the powerplant was built into the rock massif of the Quintner Formation (Quinter limestone). Pini Swiss Engineers, together with KBM Engineers SA, are involved as an engineering consortium in project design and technical construction supervision.

Technical data

  • Geodetic head: ca. 710 m
  • Junction tunnel: 4'000 m
  • Transformer cavern: 79'000 m3
  • Turbine cavern: 124'000 m3
  • Total excavation volume: 550'000 m3


Ca. CHF 500 Mio.




Axpo AG, Baden


  • Tender design
  • Construction design
  • Implementation

Date: 25.01.2019