Norway proposes radical new underwater tunnel that could halve travel time across fjords
A state of the art underwater tunnel is among a series of alternative transport options being investigated between Norway’s system of fjords that run between Kristiansand and Trondheim.
Project Coastal Highway Route 39 is exploring the technological challenges and social impacts of establishing a ferry-free road connection between the two areas.
The E39 extends for nearly 1,100 kilometres and across seven fjords which currently must be crossed by ferry.
Calls for permanent links across the fjords have led to the Norwegian Public Road Administration launching a technological development project to assess the requirements for alternative crossing systems.
Three different bridge designs are currently being investigated, including a floating structure, a giant single spanned suspension bridge and a submerged floating tunnel. The Sognefjord is currently being used as a pilot site to test plans. At 4km in width and with vast depths, it is considered the most challenging fjord to cross.
A suspension bridge between the divided land masses is one of the ideas that has been proposed. It would have a main span of 3700 metres, almost three times the length of the famous Golden gate Bridge in San Francisco and double the current world record length.
A floating structure is another idea that would see a triple spanned suspension bridge being put in place, with two of the bridge towers being placed on floating pontoons anchored to the sea floor.
The third ambitious proposal entails the construction of a submerged tunnel. This tunnel would consist of two curved concrete tubes floating 20 metres below the surface.
In addition to this, the project will consider how the road and bridge infrastructure can be utilised to generate power from solar energy, currents, waves and wind.