How will the New Tyne Crossing be built?

To the north and south of the River Tyne, the tunnel will be constructed using a technique known as 'cut and cover'. (See the menu on the right.)
 
Under the river, the tunnel will be constructed by the 'immersed tube' technique, which will connect with the cut and cover tunnels at the river banks.

The immersed tube tunnel sections will probably be constructed of concrete. Four tunnel sections, each approximately 90 metres long, are likely to be required for the immersed tube.

A trench will be excavated into the river bed using appropriate conventional dredging techniques. The sections will be floated out into the river and carefully positioned into the trench one at a time. Each section will be joined to its neighbouring unit and each end of the tube will then be connected to the cut and cover tunnels north and south of the river.

The cut and cover construction will involve maximum excavations of approximately 20 metres deep in North Tyneside and 30 metres deep in South Tyneside.