Floating tunnel to be assessed for Northern Ireland ‘fixed link’

Two former ICE presidents have been brought in to carry out an official feasibility study of a possible Irish Sea crossing, according to New Civil Engineer, and one of the options is a floating, yet submerged, tunnel.

Douglas Oakervee and Gordon Masterson have been asked to carry out an official study, following recommendations made by Sir Peter Hendy in his interim report on Union Connectivity, which examined connections between the different parts of the UK.

The interim report concluded that further work should now be undertaken to look at a ‘fixed link’ across the Irish Sea.

Numerous proposals for bridges and tunnels have been suggested.

The most recent, reportedly supported by No10, involves building an underground roundabout beneath the Isle of Man connected by three separate tunnels from England, Scotland and Northern Ireland, similar to one in the Faroe Islands.

The High Speed Rail Group proposed a cross-Irish Sea rail tunnel with connecting rail links to Carlisle and Belfast, while transport think tank Greengauge 21 has also called for the creation of a Scotland-Northern Ireland tunnel which it says could form part of a ‘capital cities axis’ between Dublin, Belfast, Glasgow and Edinburgh, according to New Civil Engineer.

Floating underwater tunnel

A floating underwater tunnel linking Scotland and Northern Ireland has also been put forward as an alternative, says New Civil Engineer.

The tunnel would run from Portpatrick in Scotland to near Larne in Northern Ireland, 50 metres below the surface of the sea.

A team from Heriot-Watt University in Edinburgh has been working on the concept, which involves the creation of a ‘submerged floating tube bridge’. This would be anchored to the sea bed and tethered to pontoons on the surface.

Cars could either drive through the tube or use a shuttle train, cutting the current two-and-a-half-hour ferry journey to 40 minutes.

A bridge, says the Daily Mail, is no longer the engineering community’s favoured option, as gale-force winds in the Irish Sea would force any such link to be closed for around 100 days a year.

It says the revolutionary £12.3bn ‘submerged floating tube bridge’, which would sit 50 metres below the surface, supported by a system of pontoons and anchors, is gaining support. At that depth, its proponents point out, ‘the water is very constant and calm’ and so bad weather is not an issue.

Submerged tunnel is feasible

“There’s no doubt that a submerged tunnel link would be feasible,” professor Guy Walker, head of the pioneering education department at Edinburgh’s Heriot-Watt University, which has produced a report on the concept, told the Daily Mail. “We’ve done the sums and we have worked out that four million people would use it every year. It is expensive, but then large infrastructure projects always are. Eventually, it would pay for itself.”

Not only would a tunnel floating below the surface allow for the free passage of ships above it and submarines above and below it, but it also promises to be the cheapest option by far, says the paper.

The floating tunnel idea may be radical but it is inspired by a project under way in Norway.

Oslo is funding a £30bn project designed to halve the time taken to make the 700-mile drive between the cities of Kristiansand in the south and Trondheim in the north.

That plan, reports the Daily Mail, is to use bridges, conventional tunnels and a submerged roadway (concrete tubes running about 30 metres below the water’s surface).

The proposed Celtic crossing would be considerably more challenging, consisting of a 28-mile subsea section. It will have to contend with Beaufort’s Dyke – two miles wide and 213 to 304 metres deep – which was used as a munitions dump after World War II.

The Hendy review will deliver its findings in the summer.

Check out a full size copy of the Daily Mail’s graphic of the design.