Weyermannshaus – Lorraine, Thrust Boring DN 400, Microtunnelling DN 1000 and DN 1200

Within four years two new transmission lines were constructed to ensure the supply of gas and water to the city of Bern. Work was largely implemented using conventional trench construction methods on cantonal and local roads. Trenchless pipe construction methods were used to cross under the River Aare with 2 DN 1000 microtunnelling and the the crossing of a railway bridge and a cantonal road using MCT DN 1200 for the gas transmission line and cable conduit block, respectively. In addition, crossing below an accessible electricity tunnel with 2 DN 400 using thrust boring for the gas and water transmission lines.

Main Data

Thrust boring DN 400

  • Length of pipeline     2 x 12m

Microtunnelling DN 1000

  • Reinforced concrete 1,280x140mm
  • Length of pipeline    2 x 65m

Microtunnelling DN 1200

  • Reinforced concrete 1,490x245mmm
  • Length of pipeline    180m
  • Gradient    28%


Energie Wasser Bern


IUB Engineering AG

Construction period


Construction costs

CHF 23 million

Scope of services

  • Design for construction
  • Tendering
  • Execution project
  • Construction management