A CONNECTING land route between Scotland and Northern Ireland, which was proposed by UK Prime Minister Boris Johnson, has been rejected as part of a feasibility study.
The study looked into the possibility of both a bridge and a tunnel, but costs are estimated to be too great for the project to proceed.
Chairman of Network Rail Peter Henry, who led the report, found that a bridge would cost an estimated €396bn (£335bn ), while a tunnel would be around €247bn (£209bn).
The report found that while both a tunnel and bridge are "technically feasible to construct," they would be the longest undersea tunnel or the longest spanning bridge in history.
It also looked to recent major UK construction projects to estimate that with planning, design, parliamentary processes, it would be unlikely the project could commence for at least ten years, followed by a minimum of 17 years of design, construction and commissioning.
"Therefore, unless some extraordinary steps were taken, it is unlikely that new transport links would be commissioned, constructed and opened for at least 25 to 30 years," Hendy said in the report's foreward.
Looking at the positives of the project, he said that while it would generate tremendous demand on construction and engineering supply chains, "if properly planned and incentivised, [it] could revitalise parts of the United Kingdom’s industry."
The project would likely give rise to more than 35,000 new jobs and apprenticeships for the design and construction phase alone.
However, he concluded that the cost of constructing either a bridge or tunnel "would be impossible to justify" even thought the economic and social effects could be transformational.
"Future transport technological advances, particularly autonomous vehicles, could allow for different tunnel and bridge designs, which could enable the construction of a fixed transport link and approaches at a lower cost," he continued.
"For now, though, the benefits could not possibly outweigh the costs to the public purse. It is therefore my recommendation to Government that further work on the fixed link should not progress beyond this feasibility study."
Other challenges posed for the construction of a bridge would be Beaufort’s Dyke (an underwater trench on the most direct route between Scotland and Northern Ireland), where "in the order of a million tons of unexploded ordnance may have been dumped."
"This area would need to be carefully surveyed and the necessary mitigation built into the project plan," the report said.
Despite an overall rejection of the idea of building a connection between the two countries, Hendy said it was "an excellent question" for Boris Johnson to ask.
"For many decades, politicians and engineers have debated this proposal, but have done so without the evidence to show whether it was possible and, if so, what it would take to do it," he said.
"This is the first comprehensive, conclusive study on the subject since the idea was first mooted over 150 years ago."
Johnson first asked Hendy to lead the Union Connectivity Review, part of which the feasibility study makes up, in October 2020.
The Prime Minister had also raised the idea of the bridge in December 2019 with then-Taoiseach Leo Varadkar in, who said the idea was "worth examining" but insisted that the UK must pay for it.