Will The Next Tyne And Wear Metro Extension Be Underground?

 

There has been much discussion recently about the prospect of an underground rail system being established in Manchester, but that may not be the only place where new Metro services involve tunnelling.

 

Whereas the Greater Manchester plans involve adding to the surface train and tram systems across the city region, the Tyne and Wear Metro is a system that combines elements of both light rail such as Manchester’s Metrolink and underground services like those seen in London and Glasgow.

 

At present, attention is being focused on a 13km surface extension of the Metro, which will link up Washington. Although it is technically now part of Sunderland, Washington, taken on its own, is the largest town in England without a railway station. A new loop will use the old track bed left derelict after the Beeching Cuts.

 

More Extensions Planned

However, proposals are also being drawn up for further potential extensions to the system, some of which could involve one of the tunnelled sections being extended.

 

These were contained in a report produced late last month by the overview and scrutiny committee of the North East Combined Authority, stating that the body is “actively exploring plans to continue to develop the Metro and local rail network for more stations and future expansion”.

 

Of the nine fully underground stations on the Metro, six lie in central Newcastle, with one in Gateshead and two in Sunderland. A notable gap in the system is the west side of Newcastle, while there is also potential to connect the (appropriately named) Metro Centre in Gateshead.

 

Going Underground To Go West

A possible means of extending the system in this area would involve taking the line beyond the current dead-end halt at St James, an underground stop that serves Newcastle United’s football stadium.

 

This would mean any westward extension from here would be underground, at least to begin with, as the area immediately west is very built up and densely populated.

 

The same is likely to be true if a westward extension began at Central Station, which is also an underground Metro stop, given its location amid the Georgian streets of the city centre.

 

What exactly is planned will be laid out when the area’s rail strategy document is published, but if more tunnelling is required, this may require large tunnel boring machinery and also the help of conveyor belt repair services to enable the extraction of material to be swift.

 

If such plans go ahead, it could be based chiefly on perceived need, likely high passenger usage and the geographical anomaly of such a large part of Newcastle being excluded from the Metro.

 

The Experience Of Other Cities

As ever, it remains to be seen if expansion plans will get the green light. Underground metro system tunnelling outside London remains rare.

 

While Andy Burnham dreams of a Mancunian underground, he may be wary of the experience of former Bristol mayor Marvin Rees, who advocated such a system for the city but gained little political support, with West of England region mayor Dan Jarvis vetoing the idea. There may be similar caution in the north east.

 

Others might note the experience of Glasgow, which was the third city in the world to establish an underground in 1896 (just a few months after Budapest became the second), but has never extended it beyond the 15-station circle. 

 

In the Glaswegian case, the latest plans are for a ‘Clyde Metro’, which will incorporate the existing Subway but be a mixed system, some of it modern trams with street running like those seen in Edinburgh, plus some repurposed rail lines, which the Tyne and Wear Metro and Manchester Metrolink have both done.

 

This could mean more underground metro services in Glasgow and at least some new or renovated tunnels. Others would involve taking over the current city centre mainline heavy rail lines that pass underground, which are more akin to the Merseyrail network in Liverpool than the Subway or the London Underground.

 

Why The Tyne And Wear Tunnels Were Built In Different Ways

Rail and metro tunnels were first excavated in Glasgow, London and Liverpool in the 19^th century. In the Tyne and Wear case, it was in the 1970s, but, despite all being dug around the same time, the Newcastle and Gateshead tunnels were built in different ways and are differing shapes.

 

This is due to geological variance, with Newcastle’s boulder clay being well suited to a traditional tube shape. By contrast, the Gateshead tunnel needed a stronger arch shape to deal with its softer sandstone bedrock and the nearby presence of old coal mines and the construction process was more painstaking.

 

Whatever tunnelling techniques might be needed for any extension, having an efficient conveyor belt will ensure the material itself is soon ferried away.