THE SCOTTISH Secretary has said he believes a fixed link between Northern Ireland and Scotland will still be possible, when self-driving cars are widely used.

Alister Jack also defended the decision to spend almost a million pounds to prove that the ‘Boris bridge’ idea would not be feasible.

The UK Government spent £900,000 on expert assessment of the so-called Boris bridge, which was either a bridge or tunnel which would connect Scotland to Northern Ireland, before determining it would cost as much as £200bn to realise, and may require feats of engineering not yet developed. It was described by some critics as “the world’s most stupid tunnel”.

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The assessment formed part of the Union Connectivity Review by Sir Peter Hendy, which looked at how all parts of the country could be better joined up. The most significant area for improvement identified by experts was the A75 trunk road, which links Cairnryan port to southwest Scotland and beyond in to England.

During a trip to Belfast last week, The Herald asked Mr Jack if he thought the £900,000 spent on assessing the Boris bridge could have been better spent, for example on upgrading the A75.

The Scottish Secretary had been visiting Belfast port to hear from hauliers and ferry firm Stena Line about the road’s poor condition, and how companies were moving operations away from Scotland as a result.

He said: “No, I don’t think that.

“At the time, it wasn’t a bridge, it was a tunnel that was being assessed.

“Those that said the Channel Tunnel wasn’t possible, for generations, were proved wrong and they have a Channel Tunnel.”

Mr Jack also said the UK Government wanted to “establish the facts” after leading architect Professor Alan Dunlop suggested the connection could cost £15-20bn.

The Scottish Secretary added that the expensive estimated bill for the proposed project was due to the infrastructure changes needed on both sides of the link.

He said: “It’s not so much just the cost of the tunnel, it is the cost of the infrastructure of both ends.

“That’s why it’s £200 billion, and 10 times what we were told, but we know now we can put it to bed.

“The ferry companies can invest with confidence in the future, because they know that people are going to be using the ferry for generations to come, so it hasn’t been a complete waste of time.

“And actually, to the people who are running those businesses, it’s quite hard for them to go to owners wherever they may be… Stena Line, the owners I think are in Scandinavia, you know, and say ‘We want to invest in new ships’ and they’ll go ‘We hear the government’s thinking about putting in a fixed link, and therefore the ferries will be redundant’.

“That gives certainty now to Stena Line that they can keep investing in the facilities here and on the other side because they know now the feasibility study has proved that the bridge or tunnel, and particularly the tunnel, are too expensive.”

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Despite the review concluding that such a project was more likely to cost around 10 times as much as Professor Dunlop had suggested, Mr Jack said a tunnel is still “very doable” as a future project, provided self-driving cars were used.

He explained: “One day, if you have fully automated cars, driverless cars, actually, the tunnel probably is feasible.

“The driverless cars drive underground for 38 miles to the other side and the passenger is not getting tired and not having an accident, because we believe driverless cars don’t crash into each other.”

Mr Jack said the plan could happen “one day in the distant future”, although he stressed that, due to all of the other infrastructure costs associated with such a link, it could not be contemplated at the moment.

He continued: “When you have to put in all the rail structure and all the other costs, that’s when it became completely unfeasible.”