St Petersburg to build world's largest bored tunnel

Photo: Claus Lunau
Construction of the 19-metre diameter bored Orlovski Tunnel in St Petersburg, Russia will begin in late 2011. COWI has been selected as engineer to examine the tunnel project’s documents and conduct an independent design assessment

The new Orlovski Tunnel is designed to alleviate traffic congestion in Russia’s second largest city, St Petersburg. Measuring just over one kilometre long, the world's largest bored tunnel will allow traffic to flow freely without disrupting shipping on the Neva River. Some 60,000 vehicles are expected to pass through the tunnel daily when it enters service in 2016.

Grand investment for St Petersburg

The Orlovski Tunnel is an enormous investment for Russia as well as the city of St Petersburg. The cost estimate will be updated in the autumn of 2011 when it has been approved by the State Expertise.

COWI engineer on world's largest bored tunnel

The tunnel’s owners, Neva Ltd Concession Company and the City of St Petersburg, have selected COWI as engineer on the tunnel project.

The bored tunnel’s width of 19 metres makes it the world’s largest. To excavate this tunnel, a specially built tunnel boring machine will be built by Herrenknecht in Germany. The contract between Herrenknecht and the concessionaire was signed in July 2011.

The adjoining onshore structures include huge shafts needed for launch and retrieval of the tunnel boring machine and up to 50 metre deep excavations for the cut and cover tunnels.

Tight deadline for complex bored tunnel project

COWI's specialists are to examine the project’s documents and conduct an independent design assessment of the bored tunnel.

More specifically, this includes an engineering review, commenting on geological and hydro-survey findings as well as conducting independent structural calculations and verifying designs for the tunnel's ventilation and drainage systems.

COWI's services should be completed well in advance before construction begins by the end of 2011.

LAST UPDATED: 03.02.2017