With the construction of a new pipeline by the Transitgas AG from the Netherlands to Italy that delivered about 75 percent of the Swiss gas market, an old pipeline in the Sörenberg region (Canton Luzern) was to be replaced by a new pipeline. The new pipeline's alignment was planed to cross under the Sörenberg instead of running though a moor like the old one from the 1970s. The tunnel has a total length of 5.2 kilometers and climbs at a gradient of five percent. The tunnel was first to be lined with concerete segments and afterwards the gas pipeline was to be installed.
The challenge for the Herrenknecht Singel Shield TBM: rock formations such as “Sörenberg melange” (clay and marl slate), flysch and globigerina marl and, furthermore, the risk of encountering gas-emmitting rock. The hardrock TBM was equipped with a gas-detecting system that would warn the tunnel crew and would shut of electricity automatically, leaving only ventilation, emergency light and telephone in operation. From August 2000 until June 2011, the machine excavated the tunnel up to the successfull breakthrough.