Italy, Livorno
2010 – 2011

In the Italian Mediterranean Sea, a former liquefied gas tanker is installed as a permanent marine terminal 22.5 kilometers off the coast from the Tuscan city of Livorno. The plan is that cargo ships dock here in the future to supply LNG - Liquefied Natural Gas. LNG only has a 600th of the volume of natural gas and can be shipped in a space-saving manner. The gas will then be regasified at the new terminal and transported as natural gas via pipelines to the mainland and into the distribution network.

The challenge: the first pipeline kilometers from the Port of Livorno must be installed beneath the Canal of Navicelli, among other things, because of space constraints. The solution: trenchless mechanized tunnelling is the right choice to keep earth works to a minimum and ensure safe tunnelling at the same time. Five AVN machines from Herrenknecht - precisely navigated using a VMT system - will install a concrete tube with varying diameters over the total length which will later on accommodate the 800-mm steel pipeline. The automatic bentonite lubrication system was mixed with a special additive to counteract salt water influences.

OLT Offshore LNG Toscana

Data Sheet

Country, Location

Italy, Livorno


2010 – 2011




Heterogeneous ground
Fine sand, loam with organic material, chalk with glimmer

Tunnelling length

5,020 m

Machine Data

2x AVN Machine:
Diameter: 2,400 mm
Lining method: Pipe jacking

1x AVN Machine:
Diameter: 2,160 mm
Lining method: Pipe jacking

2x AVN Machine:
Diameter: 1,960 mm
Lining method: Pipe jacking

Your contact person Contact us

Steffen Dubé President and General Manager Herrenknecht Tunnelling Systems USA Inc.
Gerhard Goisser Commercial Manager Herrenknecht Tunnelling Systems USA, Inc.