The Ulster Bridge

Is it then to be a bridge? A tunnel? A floating tunnel? For cars, or trains, or bicycles?

In one of the richest nations of the Earth, such an endeavour is not beyond consideration, but for over a hundred years the idea of a fixed bridge across the North Channel to join Great Britain to Ireland has always been in the ‘too hard’ tray. Now it is being looked at again, and I should emphasise ‘being looked at’ not ‘being done’.

The Channel Tunnel works because it was built with private funds with a view to profit from the services running through it.  Spaffing taxpayers’ money at a project is the best way to ensure wastage, overruns and a poor quality build. The Ulster Bridge or Ulster Tunnel (more of which later) will be too important a piece of infrastructure to leave it in the government’s ham-fisted paws.

Has anyone asked Elon Musk?

The Chinese would whack something across the sea with barely a thought, and hope it does not fall down when a Party official was driving over. We would expect the job to be done properly, the penalty for failure being fines from the Health and Safety Executive or, worse still, financial loss.

It does seem strange that with all the vast engineering projects spanning the world and in fact going  beyond it, all the millions of miles of tunnels, viaducts, cable networks, trans-continental pipelines and buildings that reach the sky raised in merely months, that our own little ditch is not bridged. Many longer tunnels have been built.

It is not as if the idea has not been considered before. In the 1890s there was a serious proposal published for a submersed floating tunnel anchored at Whitehead (south of Larne) and at Portpatrick.  Every generation since has seen ideas come and go. Today we are told to think of a bridge; tomorrow it may be a tunnel.  Engineers tell me that this idea is one which the large civil engineering companies will have as concept pieces in back drawers somewhere, and the sort of thing they hand to trainees as exercises. More than a few back drawers will be rattling open now.

The unique qualities of the North Channel, both natural and man-made, make it a new challenge.  The tunnel beneath the English Channel is no longer than one beneath the North Channel would need to be, but it is a bore largely through sand and under a shallow sea: the North Channel has hard rock and a deep sea trench with possible geological instability. Beaufort’s Dyke right in the course of where a tunnel or a bridge would go, dives to a thousand feet below sea level (although it may be possible to find a point “only” 500 feet down) and, just for further amusement, after the War more than a million tons of unused ordnance was dropped into it: you do not want a million tons of unstable shells and bombs beside the footings or a bridge or above a deep tunnel.

This assumes that the tunnel or bridge would cross the North Channel at the main ferry point, between the east coast of Antrim (or Down) and the Rhinns of Galloway, which is a twenty-two mile crossing (one I have sailed in a dead calm and in a storm). Another route is from the north coast of County Antrim to the Mull of Kintyre. That is so short a distance that I could stand on the Argyll side and watch the cars in Antrim, and the Beaufort Trench is not there. Once there was a ferry (with a Brussels subsidy, naturally) sailing from Campbeltown to Portrush – it closed because there was no custom, and that is the problem with this route – not just that it would wreck two beautiful, peaceful spots, but it is from no commercial place to no commercial place.  Maybe a twelve-mile Argyll-Antrim tunnel would create its own dynamic, but it is just the wrong place.

Back to structures, and I said it was a choice between bridge and tunnel; the mock-up used in the press release has a remarkable variant:  a tunnel from Larne beneath the main shipping lane, emerging in the sea to rise up onto a bridge! That is reminiscent of one of the odder plans for a road crossing of the English Channel, with bridges out into the sea ending in spiral ramps down to a tunnel.

The plan in 1890 was a serious one, for a rail link using a tunnel, a submerged tubular bridge or a solid causeway, or it might be a mixture, and the engineer who proposed it was no dreamy student but the great Luke Livingston Macassey, who created Belfast’s fresh water system, and he had been working on it since the 1860s. An article can still be found somewhere in the archives, and it is recalled in a book ‘Mapping the Railways’ (see below).

It is an intriguing thought: a tunnel carved in the normal way until the sudden 500-foot deep then carried on an undersea bridge. The bridge would be subject to the corrosion of the sea and to the deep-sea currents for which the North Channel is known, but not to the tides or storms, as an exposed bridge would be, and having been tossed about in those storms myself, I would feel more comforted being carried snug beneath them.

Modernity solutions for unusual engineering solutions. Those proposing new manned landings of the Moon or a base on Mars have suggested first sending autonomous robots to build substantial accommodation ready for the star-sailors who will follow. If it is possible to have robots build complex structures in extra-terrestrial locations, without needing rest, undaunted by time, then to send them tunnelling beneath the sea and building a causeway across the trench seems no great stretch. If they take twenty years, well, we have been waiting a hundred and fifty already. I am no engineer, but it seems reasonable to assume that if ‘bots could build and shore-up even a narrow tunnel and place rails within it, that provides a transport link that can start earning its keep, and the link necessary to dig a wider tunnel.

As to the unexploded munitions, that is another puzzle. Is there a market for deep-sea mining of the iron and chemicals constituted in those discarded weapons? Here too robots have a place as they may be more disposable than flesh and blood miners and do not have to come up for air.

The economics prescribe that the tunnel or bridge would most probably be for a railway not a road (a foot and cycle tunnel beside it would be appreciated by vigorous travellers, but we didn’t get it in the tunnel to France). A practical point though: the railways of Great Britain and of most of Europe are all of the same rail gauge, 4 feet ​8 12 inches, which is why the Channel Tunnel can enable a train to run from Inverness to Constantinople, but the Irish gauge is 5 feet 3 inches. That then would require a transhipment port at one end or other of the tunnel, or some dual-gauge track to such a node, or tearing up and relaying all the railway lines across Ulster and Ireland, or a curse on both their houses and doing it as an vacuum-tunnel maglev system.

There are many intriguing ideas to be thrown about in the next few years and many dead-ends, but it must be considered.

See also

Books

Author: AlexanderTheHog

A humble scribbler who out of my lean and low ability will lend something to Master Hobbes

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