How Irish Sea tunnel proposed in 60s became just another pipe dream

Proposed tunnel from Northern Ireland to Scotland

A proposal for a tunnel between Northern Ireland and Scotland was raised with then Northern Ireland PM Captain Terence O'Neill in the 1960s

Proposed tunnel route

Tunnel assembly

Tunnel shore assembly station

Just a few years before the outbreak of the Troubles, the old Northern Ireland government examined the possibility of a tunnel to Scotland in which driverless electric trains moved back and forth each hour - but quickly abandoned the idea due to the enormous cost.

The idea of a physical link between the island of Ireland and Great Britain had existed since Victorian times but newly-declassified government files show that it was resurrected in the 1960s - more than half a century before the DUP and then Boris Johnson suggested such a grand project.

A proposal for a tunnel between Northern Ireland and Scotland was raised with then Northern Ireland PM Captain Terence O'Neill in the 1960s

Professor AA Wells, chair of structural science at Queen’s University Belfast, was an enthusiastic proponent of the undersea link and wrote to the Stormont government on a confidential basis in 1964.

He proposed a single rail track tunnel to run from Float Bay on the Galloway shore to a short distance south of Donaghadee, a distance of 23 miles, with an electrified track linked to Bangor on one side and British Railways on the other side.

He suggested the electrified track could double as an electricity interconnector between Scotland and Northern Ireland, and also carry a gas interconnector. An independent gas interconnector was opened in 1996 and an electricity link in 2001.

Tunnel shore assembly station

Prof Wells suggested that his “sea bed tube” design could cost about £35m (£587m in today’s money) and be built in three years after three years of planning with just 50 workers on each shore.

He suggested it could carry 1.1m passengers and 600,000 cars in 1971, its first year of operation, before increasing to 2.64m passengers within 20 years.

He proposed this would be profitable to private companies if the Stormont and London governments would pay for the cost of building the structure.

He set out in some detail how the aluminium alloy tube lined with concrete blocks could be pushed out from each shore to meet in the middle, resting on a bed of concrete. But the professor disconcertingly admitted that he had only been able to do “small scale experiments”...with his garden hose. Nevertheless, he was confident “there would appear to be a wide margin of safety against buckling”.

He suggested the trains could be driverless under “intrinsically fail-safe conditions”.

To convince the public that his design was safe, he proposed dropping a sealed section of tube and subjecting it to depth-charging.

Tunnel assembly

One official was sceptical about Prof Wells’s case for the tunnel, saying he had exaggerated the case for it by overstating the problem of sea or air crossings cancelled by bad weather.

He said the economic assumptions behind the case for the tunnel were based on the premise that virtually all passenger traffic would transfer from sea and air to using the tunnel. The official wrote: “Personally, I would very much prefer to travel by sea or by air than by a long rail tunnel and I doubt very much if I would be alone in this respect.”

John Semple in the Offices of the Cabinet of Northern Ireland - a future head of the civil service - wrote in November 1964 that the first step was to see if a tunnel costing £35m could possibly pay; if so, they could examine the technical case for whether it could be constructed for that sum.

He referred to “the rather crude and grossly over-optimistic traffic estimate” from Prof Wells and said that if the economic case was insurmountably negative then he thought they should not encourage the professor and Queen’s University’s engineering department “to develop new techniques which will almost certainly never be used”.

On the plus side, Mr Semple considered that the tunnel would provide intangible economic and social benefits to Northern Ireland. It would provide more reliable connectivity with Britain, improving Northern Ireland’s access to the British market and stimulating tourist growth by making it easier for tourists to get to Northern Ireland.

The cost of imports to Northern Ireland might be reduced and social connections - both for the public and those in business - would be improved.

On an optimistic assumption, £2.4m might be gathered in revenue from the tunnel in its first year of operation in 1970, he said (at £2 a car), rising to about £5m a year in 1990. But he concluded that even in this scenario, the project would be uneconomic.

Proposed tunnel route

A report in the News Letter at the time noted immediately the constitutional significance of such a venture, saying that if the tunnel could be built “the psychological factor of Ulster being cut off from the rest of the British Isles would disappear”.

Another official said it had been examined by his technical colleagues and “there is nothing inherently impossible in the various ingenious techniques which are embodied in [the proposal], though the fact that they are theoretically possible does not mean that difficulties could not arise in practice”.

Ken Bloomfield, another future head of the civil service, was involved, saying in a 14 September 1964 memo: “The Prime Minister has now returned from his continental visit and I have shown him your letter about the project for a tunnel link between Northern Ireland and Scotland.

“Captain O’Neill feels that you could best discuss this matter with the Minister of Health and Local Government, Mr WIlliam Craig.”

On 1 September 1964, Mr Bloomfield wrote to a colleague that “although the whole idea of a tube link between Northern Ireland and Scotland seems to the layman to be rather far-fetched” a US firm called Technical Studies Inc had expressed interest and it “seems…to be backed by a number of extremely reputable American financial and other organisations.”

An earlier memo from Stormont’s chief engineer in February 1964 said that the issue had been raised in the Senate in 1954 but the problems remained the same.

“The difficulties of draining, ventilating and lighting a tunnel 28 miles long could probably be overcome at a high cost, but the problem of obtaining accurate information of the strata to be encountered below the sea bed, at a depth of at least 450ft, and possible 900ft, below sea level, has not yet been solved.

“Also, present methods of tunnelling are not applicable to places where water pressures of up to 500lb per sq inch may be met”.

He added: “I would be well to remember that the area in and around Beaufort’s Dyke was used as a dump for surplus explosives during and after the last war and these would certainly add to the hazards of any operation in this area”.

The file also contains a clipping from the Belfast Telegraph in 1963 headlined “Butcher has plan for pipe link”, reporting that Moira butcher George McCartney had been campaigning for a GB-NI tunnel but had switched his idea to “a pipeline as an alternative”.

Daily Headlines Newsletter

Receive today's headlines directly to your inbox every morning and evening

Please check your inbox to verify your details