The Canal Tunnels are a pair of single track railway tunnels in north
London
London is the capital and largest city of England and the United Kingdom, with a population of just under 9 million. It stands on the River Thames in south-east England at the head of a estuary down to the North Sea, and has been a majo ...
which connect the
East Coast Main Line
The East Coast Main Line (ECML) is a electrified railway between London and Edinburgh via Peterborough, Doncaster, York, Darlington, Durham and Newcastle. The line is a key transport artery on the eastern side of Great Britain running broa ...
to
London St Pancras International Thameslink. Their name comes from the
Regent's Canal
Regent's Canal is a canal across an area just north of central London, England. It provides a link from the Paddington Arm of the Grand Union Canal, north-west of Paddington Basin in the west, to the Limehouse Basin and the River Thames in eas ...
, which they pass closely beneath.
Constructed as one element of the overarching
Thameslink Programme
The Thameslink Programme, originally Thameslink 2000, was a £6billion project in south-east England to upgrade and expand the Thameslink rail network to provide new and longer trains between a wider range of stations to the north and to the s ...
, the Canal Tunnels enabled trains to travel directly from
Peterborough
Peterborough () is a cathedral city in Cambridgeshire, east of England. It is the largest part of the City of Peterborough unitary authority district (which covers a larger area than Peterborough itself). It was part of Northamptonshire until ...
and
Cambridge
Cambridge ( ) is a university city and the county town in Cambridgeshire, England. It is located on the River Cam approximately north of London. As of the 2021 United Kingdom census, the population of Cambridge was 145,700. Cambridge bec ...
to St Pancras, along with numerous other stations in London,
Gatwick Airport
Gatwick Airport (), also known as London Gatwick , is a major international airport near Crawley, West Sussex, England, south of Central London. In 2021, Gatwick was the third-busiest airport by total passenger traffic in the UK, after H ...
and down to
Brighton
Brighton () is a seaside resort and one of the two main areas of the City of Brighton and Hove in the county of East Sussex, England. It is located south of London.
Archaeological evidence of settlement in the area dates back to the Bronze A ...
and
Horsham
Horsham is a market town on the upper reaches of the River Arun on the fringe of the Weald in West Sussex, England. The town is south south-west of London, north-west of Brighton and north-east of the county town of Chichester. Nearby to ...
. They were constructed between 2004 and 2006, while fitting-out was performed between 2013 and 2014. The first services were run through the Canal Tunnels during February 2018, while its official opening occurred three months later. The Canal Tunnels run from Belle Isle Junction, north of
London King's Cross
King's Cross railway station, also known as London King's Cross, is a passenger railway terminus in the London Borough of Camden, on the edge of Central London. It is in the London station group, one of the busiest stations in the United King ...
, to Canal Junction.
Construction
The Canal Tunnels were constructed as part of the wider
Thameslink Programme
The Thameslink Programme, originally Thameslink 2000, was a £6billion project in south-east England to upgrade and expand the Thameslink rail network to provide new and longer trains between a wider range of stations to the north and to the s ...
; a £6 billion project to upgrade and expand the north-south railway crossing the capital. They were the first main limb of Thameslink to commence construction.
Their main purpose is to link the
East Coast Main Line
The East Coast Main Line (ECML) is a electrified railway between London and Edinburgh via Peterborough, Doncaster, York, Darlington, Durham and Newcastle. The line is a key transport artery on the eastern side of Great Britain running broa ...
(ECML) with the Thameslink network; a junction connecting the tunnels northern approach to the ECML is 100 metres from the northern portals.
The tunnels were designed by Halcrow Group, part of the Rail Link Engineering consortium, with safety and resilience in mind. The construction process itself took roughly two years, with civil works commencing in 2004 and completed in 2006. Design and construction of the tunnels were planned to integrate with the adjacent railway engineering works for the Channel Tunnel Rail Link
High Speed 1
High Speed 1 (HS1), legally the Channel Tunnel Rail Link (CTRL), is a high-speed railway linking London with the Channel Tunnel.
It is part of a line carrying international passenger traffic between the United Kingdom and mainland Europe; ...
and redevelopment of the Railway Lands and
St Pancras railway station
St Pancras railway station (), also known as London St Pancras or St Pancras International and officially since 2007 as London St Pancras International, is a central London railway terminus on Euston Road in the London Borough of Camden. It is ...
.
The tunnels were driven using
tunnel boring machine
A tunnel boring machine (TBM), also known as a "mole", is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata. They may also be used for microtunneling. They can be designed to bore throu ...
s (TBMs). Each bore is in diameter and lined with pre-cast concrete segmental rings. The northbound tunnel is in length, while the southbound tunnel is long; this disparity is due to curvature.
The tunnels have a maximal incline of 1 in 34; the nadir is next to the main sump system.
Power is normally from supplies for the nearby
Midland Main Line
The Midland Main Line is a major railway line in England from London to Nottingham and Sheffield in the Midlands. It comprises the lines from London's St Pancras station via Leicester, Derby/Nottingham and Chesterfield in the East Midlands.
...
however provisions to use those of the ECML were made.
For safety reasons, emergency service radio systems have been installed, along with a walkway and automated
LED
A light-emitting diode (LED) is a semiconductor Electronics, device that Light#Light sources, emits light when Electric current, current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy i ...
lighting at four-metre intervals for an escape route for any passenger evacuation of the tunnel. On account of the Regent Canal being above, flood management measures were built, including a drainage system with a large sump beneath the tunnel, which is pumped into the ECML's drainage system.
The infrastructure has been designed to facilitate bi-directional working for greater operational flexibility.
Despite their problem-free completion, the Canal Tunnels remained unused for several years. This was largely due to their having been completed well in advance of numerous other Thameslink elements, such as delivery of the new
British Rail Class 700
The British Rail Class 700 '' Desiro City'' is an electric multiple unit passenger train capable of operating on from overhead wires or 750 V DC from third rail. 115 trainsets were built between 2014 and 2018, for use on the Thameslink net ...
multiple unit
A multiple-unit train or simply multiple unit (MU) is a self-propelled train composed of one or more carriages joined together, which when coupled to another multiple unit can be controlled by a single driver, with multiple-unit train contr ...
s ordered for the service and other infrastructure works.
During this interval, the installation of track, power supply, and signalling systems were performed ahead of the commencement of passenger services. In August 2012, railway infrastructure owner
Network Rail
Network Rail Limited is the owner (via its subsidiary Network Rail Infrastructure Limited, which was known as Railtrack plc before 2002) and infrastructure manager of most of the railway network in Great Britain. Network Rail is an "arm's leng ...
announced that the construction company
Carillion
Carillion plc was a British multinational construction and facilities management services company headquartered in Wolverhampton in the United Kingdom, prior to its liquidation in January 2018.
Carillion was created in July 1999, following a ...
had been appointed as the principal
contractor
A contractor is a person or company that performs work on a contract basis. The term may refer to:
Business roles
* Defense contractor, arms industry which provides weapons or military goods to a government
* General contractor, an individual o ...
for the fitting-out of the Canal Tunnels.
The fitting-out process commenced during 2013 and was completed during the following year, despite this milestone occurring several years ahead of services running; this was reportedly to facilitate stock movements and to take advantage of available land to facilitate such work.
The signalling systems installed were integrated with Thameslink's High Capacity Infrastructure; in addition to conventional colour light signalling, the
European Train Control System
The European Train Control System (ETCS) is the signalling and control component of the European Rail Traffic Management System (ERTMS). It is a replacement for legacy train protection systems and designed to replace the many incompatible s ...
is present; Thameslink officials claimed that this arrangement was the world's first implementation of such technology on a mainline 'heavy' railway.
Wherever possible all wiring, mechanical, and electrical equipment was cleanly run in a pair of interior troughs. Amongst the last elements of the work was the connection of the new track to the existing lines via the insertion of new junctions.
Services
On 26 February 2018, the first passenger service traversed the Canal Tunnels after many out-of-service trains had done so for testing.
The tunnels were officially opened to traffic during May 2018, forming a part of the Thameslink core route from that month onwards.
Until then, capacity had been limited to 16 trains per hour from
Bedford Midland
Bedford railway station (formerly Bedford Midland Road and historically referred to on some signage as Bedford Midland) is the larger of two railway stations in the town of Bedford in Bedfordshire, England. It is on the Midland Main Line from ...
, /
Luton Airport Parkway
Luton Airport Parkway railway station is on the Midland Main Line in England, serving south Luton and Luton Airport in Bedfordshire. It is situated in Park Town, Luton, and is down the line from London St Pancras between to the south and to ...
and
St Albans City southbound via the
Midland Main Line
The Midland Main Line is a major railway line in England from London to Nottingham and Sheffield in the Midlands. It comprises the lines from London's St Pancras station via Leicester, Derby/Nottingham and Chesterfield in the East Midlands.
...
; the presence of the Canal Tunnels added another 8 per hour from Cambridge and Peterborough, achieving the objective of a peak service of 24 trains per hour between St Pancras and
Blackfriars Blackfriars, derived from Black Friars, a common name for the Dominican Order of friars, may refer to:
England
* Blackfriars, Bristol, a former priory in Bristol
* Blackfriars, Canterbury, a former monastery in Kent
* Blackfriars, Gloucester, a f ...
.
Many of these movements are automated, making use of the route's advanced digital signalling.
References
{{Reflist
External links
Case Study on the Canal Tunnels via swordgroup.co.ukThameslink 2000 tunnels via researchgate.net
Railway tunnels in London
Railway tunnels in England
2006 establishments in England
Rail infrastructure in London