The Clyde Tunnel is a crossing beneath the
River Clyde
The River Clyde ( gd, Abhainn Chluaidh, , sco, Clyde Watter, or ) is a river that flows into the Firth of Clyde in Scotland. It is the ninth-longest river in the United Kingdom, and the third-longest in Scotland. It runs through the major cit ...
in
Glasgow
Glasgow ( ; sco, Glesca or ; gd, Glaschu ) is the most populous city in Scotland and the fourth-most populous city in the United Kingdom, as well as being the 27th largest city by population in Europe. In 2020, it had an estimated popul ...
,
Scotland
Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the ...
for road traffic, cyclists and pedestrians. Two parallel
tunnel
A tunnel is an underground passageway, dug through surrounding soil, earth or rock, and enclosed except for the entrance and exit, commonly at each end. A pipeline is not a tunnel, though some recent tunnels have used immersed tube cons ...
tubes connect the districts of
Whiteinch
Whiteinch ( gd, Innis Bhàn) is an area in the city of Glasgow, Scotland. It is situated directly north of the River Clyde, between the Partick and Scotstoun areas of the city. Whiteinch was at one stage part of the burgh of Partick, until that ...
to the north and
Govan
Govan ( ; Cumbric?: ''Gwovan'?''; Scots: ''Gouan''; Scottish Gaelic: ''Baile a' Ghobhainn'') is a district, parish, and former burgh now part of south-west City of Glasgow, Scotland. It is situated west of Glasgow city centre, on the south ba ...
to the south in the west of the city.
History
Efforts to improve the transport infrastructure of Glasgow post-
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
were hit by the problem of crossing the Clyde. Downstream of Jamaica Street in the
city centre
A city centre is the commercial, cultural and often the historical, political, and geographic heart of a city. The term "city centre" is primarily used in British English, and closely equivalent terms exist in other languages, such as "" in Fren ...
, it was perceived to be impossible to build a
bridge
A bridge is a structure built to span a physical obstacle (such as a body of water, valley, road, or rail) without blocking the way underneath. It is constructed for the purpose of providing passage over the obstacle, which is usually somethi ...
due to the prevalence of
shipping
Freight transport, also referred as ''Freight Forwarding'', is the physical process of transporting Commodity, commodities and merchandise goods and cargo. The term shipping originally referred to transport by sea but in American English, it h ...
. The solution — to build a tunnel beneath the river — was not a new one, with the
Harbour Tunnel at
Finnieston
Finnieston is an area of Glasgow, Scotland, situated on the north bank of the River Clyde roughly between the city's Glasgow#West End, West End and the Glasgow#City centre, city centre.
Finnieston is home to the Scottish Exhibition and Conferen ...
having been built in the 1890s. However, the Clyde Tunnel project was to be built in the boom of the car era and would be a much larger project. It was given the green light in 1948 but financial difficulties prevented work from beginning until 1957.
Construction
A
tunnelling shield
A tunnelling shield is a protective structure used during the excavation of large, man-made tunnels. When excavating through ground that is soft, liquid, or otherwise unstable, there is a potential health and safety hazard to workers and the proj ...
, based on
Marc Isambard Brunel
Sir Marc Isambard Brunel (, ; 25 April 1769 – 12 December 1849) was a French-British engineer who is most famous for the work he did in Britain. He constructed the Thames Tunnel and was the father of Isambard Kingdom Brunel.
Born in Franc ...
's design used for the
Thames Tunnel
The Thames Tunnel is a tunnel beneath the River Thames in London, connecting Rotherhithe and Wapping. It measures 35 feet (11 m) wide by 20 feet (6 m) high and is 1,300 feet (396 m) long, running at a depth of 7 ...
a century earlier, was used to dig the two tunnels.
The tunnels were cut perfectly circular with the road deck sitting a third of the way up. Under each road deck is the pedestrian/cycle tunnel and ventilation ducts. 16
miners
A miner is a person who extracts ore, coal, chalk, clay, or other minerals from the earth through mining. There are two senses in which the term is used. In its narrowest sense, a miner is someone who works at the rock face; cutting, blasting, ...
operated the shield working shifts in a
compressed air
Compressed air is air kept under a pressure that is greater than atmospheric pressure. Compressed air is an important medium for transfer of energy in industrial processes, and is used for power tools such as air hammers, drills, wrenches, and o ...
environment to ensure that the rock and the river above did not collapse into the tunneling area. The digging itself would be done only with great difficulty due to the
geology
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Ear ...
of the area, hard rock sitting under a soft
silt
Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension with water. Silt usually has a floury feel when ...
layer beneath the river.
The techniques for decompression after a period of working in a high pressure atmosphere had not been perfected at this time and – also owing to the prevalence of workers refusing to go through the decompression sequence given the length of time required (around an hour) – there were a number of cases of
decompression sickness diagnosed as a result, resulting in two fatalities.
Work on the tunnel was halted for a time after an explosion when compressed air escaped through the tunnel lining into the river, flushing outward in a fountain.
The first completed tunnel tube, for northbound traffic, was eventually opened by
Queen Elizabeth II
Elizabeth II (Elizabeth Alexandra Mary; 21 April 1926 – 8 September 2022) was Queen of the United Kingdom and other Commonwealth realms from 6 February 1952 until Death and state funeral of Elizabeth II, her death in 2022. She was queen ...
on 3 July 1963, with the southbound tunnel opening in March 1964. The total cost of the project was
£10 million. By this point, the migration of port facilities downstream to the deeper waters of the
Firth of Clyde
The Firth of Clyde is the mouth of the River Clyde. It is located on the west coast of Scotland and constitutes the deepest coastal waters in the British Isles (it is 164 metres deep at its deepest). The firth is sheltered from the Atlantic ...
and improvements in
engineering
Engineering is the use of scientific method, scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and buildings. The discipline of engineering encompasses a broad rang ...
technology had allowed the consideration of bridges downstream of the city centre, namely the
Kingston Bridge and, much further downstream than the Tunnel, the
Erskine Bridge
The Erskine Bridge is a multi span cable-stayed box girder bridge spanning the River Clyde in west central Scotland. The bridge connects West Dunbartonshire with Renfrewshire and can be used by all types of motor vehicles, cyclists and pedestrian ...
.
The tunnels
The road tunnels are each 762 metres (2,500 feet) long with a
gradient
In vector calculus, the gradient of a scalar-valued differentiable function of several variables is the vector field (or vector-valued function) \nabla f whose value at a point p is the "direction and rate of fastest increase". If the gradi ...
approaching 6% or 1:16. The width of the river at this point is . Each road tunnel carries two lanes of traffic as part of the A739 road, and are completely separate except for a very small crossover passage between the road tunnels at the
nadir
The nadir (, ; ar, نظير, naẓīr, counterpart) is the direction pointing directly ''below'' a particular location; that is, it is one of two vertical directions at a specified location, orthogonal to a horizontal flat surface.
The direc ...
(barely large enough for a single pedestrian). They are monitored and controlled from the two Portal towers, one at each end of the tunnel, where
CCTV
Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs from broadcast television in that the signal is not openly t ...
monitors the entirety of the tunnel. Beneath the road tunnel decks run foot and cycle tunnels, and below those the tunnels' services.
Pedestrian and cycle tunnels
Both tunnels are open to pedestrians in both directions. The eastern tunnel is open to cyclists going southbound, and the western tunnel to cyclists going northbound. In 2008,
CCTV
Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs from broadcast television in that the signal is not openly t ...
secure entry systems were installed at the portals of these tunnels in order to reduce crime and
anti-social behaviour in the tunnels.
Repair work
The estimate for traffic levels in the tunnel was between 9,000 and 13,000 vehicles per day during construction; on the first day of opening, 22,000 vehicles used the tunnel. Current estimates for traffic levels are around 65,000 vehicles per day. These unanticipated high volumes of traffic have increased the wear rate for the tunnel, causing it to close repeatedly for repair and renovation work, which has disrupted traffic in the area for over a decade, and has arguably led to the increase in traffic causing similar problems on the Kingston Bridge.
The more recent repairs, costing as much as the initial outlay for construction, involved installing a second, modern, fireproof layer, enabling the tunnel to meet European safety standards after St Gotthard and
Mont Blanc tunnel fires, along with new air extraction systems and new
lighting
Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylig ...
. Work began in March 2005 and was scheduled to last until at least April 2006, with one of the tunnels closed during off-peak hours (19:00 to 07:00 daily). However, problems that were encountered meant the work was only completed in 2010.
The roadworks coincided with the "Hold Your Breath" project which aimed to add an
art
Art is a diverse range of human activity, and resulting product, that involves creative or imaginative talent expressive of technical proficiency, beauty, emotional power, or conceptual ideas.
There is no generally agreed definition of wha ...
istic experience to travel through the tunnel. The pedestrian tunnel also had its years of
graffiti
Graffiti (plural; singular ''graffiti'' or ''graffito'', the latter rarely used except in archeology) is art that is written, painted or drawn on a wall or other surface, usually without permission and within public view. Graffiti ranges from s ...
removed as part of a beautification project, but it was often redone soon after being removed.
Breath holding
A popular game amongst local children, and some adults, is attempting to hold one's breath for the duration of the journey by motorized vehicle through the Clyde Tunnel. This is possible due to the short length of the tunnel – a car travelling at the limit takes 57 seconds to pass through, and at off peak times traffic is often flowing at around , resulting in a transit duration of 42 seconds. Success is hampered by snarlups (particularly at the interchange on the north end) slowing traffic. The breath-holding game was the subject of Scottish artist
Roderick Buchanan's video ''Gobstopper'', for which he won the
Beck's Futures
Beck's Futures was a British art prize founded by London's Institute of Contemporary Arts and sponsored by Beck's beer given to contemporary artists.
Prior to the establishment of the prize in 2000, Beck's had sponsored several exhibitions of con ...
art prize in 2000.
[Moira Jeffrey, ''Beer faced cheek''. Breath holding within the tunnel is still popular to this day.(201]
''The Sunday Herald'', 17 September 2000
/ref>
References
External links
Glasgow Motorway Archive - Clyde Tunnel and Approaches
Clyde Tunnel page
on the Glasgow City Council website
The ''Hold Your Breath'' project
{{authority control
Tunnels in Scotland
Transport in Glasgow
River Clyde
Tunnels completed in 1963
Govan
Partick
Road tunnels in the United Kingdom
Cycling tunnels in the United Kingdom