DfT hints at new Trans-Pennine rail tunnel
The DfT has raised the prospect of a new rail tunnel under the Pennines though it remains tight-lipped about any possibility of re-opening the disused Woodhead line.
The Department has issued an updated interim report shortlisting five – out of an original 36 – routes for a new Trans-Pennine tunnel and road linking Manchester and Sheffield, which might be combined with a new rail tunnel.
The work was carried out by Highways England (HE) for the DfT and Transport for the North (TfN). The five options are to be assessed further and a final report will be issued at the end of the year.
If built, the road tunnel would be the longest in Europe and it would cost well over £1bn.
Links between both cities are poor:
“The DfT identifies linkages across the Pennines as one of the main gaps in connectivity in the North. Current road linkages between two of the main urban centres, Manchester and Sheffield, are among the worst in the country in terms of capacity, journey times, safety and reliability. This is made worse by the fact that rail connections between the two cities are also considered to be too slow,” says the report.
Compared to the Manchester-Leeds corridor, Manchester-Sheffield is very much the poor relation: By road, the distance between Manchester and Leeds is 45 miles (mainly on the M62) and takes around 65 minutes. Between Manchester and Sheffield the distance is 40 miles (by the A57, or A628, A616 and A61 Pennine routes) and takes about 75 minutes; or 75 miles/95 minutes (mainly) by the M62.
Only 10% of Sheffield journeys take the latter M62 route, and the motorway is the only major east-west road link in the north. The Pennine routes are more prone to accidents and suffer longer delays. Building a tunnel under the Pennines would nearly halve journey times between both cities, and it would also divert traffic away from the scenically attractive Peak District National Park.
A combined road and rail tunnel would produce synergies says the report. It would make some sense of Stephen Hammond’s strange 2013 decision (whilst working at the DfT) not to purchase the disused Woodhead tunnels on the grounds that building a new tunnel would be a better future option:
“If an additional rail route was ever required between Manchester and Sheffield, it is unlikely that even the modern (twin-bore Woodhead) tunnel (of 1953) would be suitable for re-use and, given advances in tunnelling technology even since 2008 as witnessed by Crossrail, the best solution is most likely to be the construction of a new tunnel .”
However Hammond also added that the possible future re-opening the Woodhead line should not be ruled out (and that is more likely to happen if the rail scheme were to be part of a wider transport plan than a simple standalone project).
The Manchester to Sheffield Woodhead route closed to all traffic in 1981. National Grid acquired the tunnels and put high voltage electric power cables inside. The two older single bore tunnels (dating from 1845 and 1852) are in poor condition and only one is currently used by National Grid. The modern twin bore dates from 1953 and was built when the line was electrified. It now forms the main National Grid tunnel.
Apart from the tunnels, a large section of the disused trackbed now makes up part of the Trans-Pennine Trail.
Train services between Manchester and Sheffield are currently served by the rival Hope Valley line. Ironically, Dr Beeching wanted to close this line in the 1960s and keep the Woodhead route open but events turned out otherwise.
The government is keen to rebalance the economy and to eliminate regional imbalance – citing lower employment rates and poor productivity in the north – as part of its Northern Powerhouse agenda. So a new Trans-Pennine road and tunnel would address wider socio-economic concerns as well as meeting a pressing transport need.
HS2 is a north to south link and does nothing for east-west connectivity; HS3 will improve connectivity, but its main emphasis will be the Manchester to Leeds corridor. Hence the appeal of the Trans-Pennine project.
A Heavy Rail option would be the most likely one:
“Heavy rail and highway traffic would require segregation in a tunnel, either vertically or horizontally. The resulting tunnel diameter required with vertical segregation would not be feasible with current TBMs (tunnel boring machines). The width required for horizontal segregation is likely to result in a tunnel span that would be at the extreme end of what is feasible even for much slower drill-and-blast construction techniques.
“We believe that with today’s technology it would be necessary to construct additional tunnel bores to accommodate a heavy rail route. The required cross section for a rail tunnel is dependent on a number of factors, including line speed, operational and safety requirements. The tunnel could be either a larger bi-directional single bore or a twin, smaller bore arrangement. The total number of tunnel bores for a combined road/rail corridor could affect the scale of the portal areas. However, the rail portal may not be located in the same position as the road portal.”
But the report is more dismissive about a Light Rail solution:
“Allowing light-rail and highway traffic to share road space on a strategic link and within a tunnel would require the adoption of technological advances and development of a robust safety case . . . Allowing light rail and road to share space within the tunnel may increase the size of the tunnel bore in order to incorporate the overhead electrification system.”
The capital cost of a new tunnel would be “well in excess of” £1bn regardless of the route chosen and it could open within 20/25 years. Depending on the route, the length would range from 23 to 36 miles, of which the tunnelled section would account for between 10 and 19 miles. All five route options would connect the M60 (east of Manchester) with the MI (north of Sheffield).
The Trans-Pennine tunnel strategic study is one of six strategic road studies being undertaken for DfT’s long term Road Investment Strategy (RIS ).