Hex River Tunnel
Encyclopedia
The Hex River Tunnels, also known as Hexton, in the Western Cape Province of South Africa
is a tunnel system consisting of four single track railway tunnels connecting De Doorns
in the Hex River valley with Touws River
in the Little Karoo.
and the Kimberley
diamond fields in the 1870s. In 1874 surveyor Wells Hood, under the instruction of the railway engineer Thomas Brounger, found a potential route up the 2353 feet (717 m) climb from De Doorns in the Hex River valley to the top of the Little Karoo plateau east of the Valley, with gradient
s of no more than 1 in 40, very steep by railway standards. In addition, he proposed that a short tunnel
would be required at the summit. Thomas Brounger's route through the Hex River Pass was selected by 1876, with the line to follow the route from Worcester
through De Doorns
, up the pass via Osplaas, Tunnel and Matroosberg to Touws River
, Matjiesfontein
, Laingsburg
and on to Beaufort West
.
(CGR) to abandon the use of Standard gauge
, which had been used for the line between Cape Town
and Wellington
, and to install the track across the pass at 3 in 6 in (1,066.8 mm) gauge. A subsequent decision resulted in all existing tracks of the CGR being converted to what was to become known worldwide as Cape gauge
.
Credit for the fact that most of the present day railway lines in Africa are Cape gauge can therefore be directly attributed to the Hex River Pass. Despite its quick and relatively cheap construction, the pass served the South African Railways for more than a century. It was the starting point of the country's first railway line to the Witwatersrand
and opened the way for Rhodes
' colonisation
thrust into central Southern Africa
.
The original tunnel, Southern Africa’s first railway tunnel, is situated at Km 34 between De Doorns and Matroosberg. Just to the east of the tunnel was a siding, approriately named "Tunnel". The tunnel portals were of dressed stone masonry, but the inside was unlined. This tunnel served the railways for 53 years, until the track was relaid in 1929 to diminish a curve in order to accommodate larger locomotives. In the process a new concrete lined tunnel was sunk alongside the original. This latter tunnel remained in use for sixty years, until the line across the pass was closed in 1989.
The bore was hardly more than about 66 feet (20 m) deep, however, when ground water flooding brought tunneling to a halt, and the project was eventually abandoned. Instead, the pass was electrified by 1954 and operated with Class 4E electric locomotives, which were amongst the most powerful electric locomotives in the world at that time.
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
is a tunnel system consisting of four single track railway tunnels connecting De Doorns
De Doorns
De Doorns, Western Cape is a settlement in Cape Winelands District Municipality in the Western Cape province of South Africa....
in the Hex River valley with Touws River
Touws River (town)
Touws River is a small railway town of 6,800 people in the Western Cape province of South Africa. It is located on the river of the same name, about north-east of Cape Town.-History:...
in the Little Karoo.
The Hex River Pass
The Hex River Pass across the Matroosberg range was a major obstacle to overcome during the construction of the railway between Cape TownCape Town
Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...
and the Kimberley
Kimberley, Northern Cape
Kimberley is a city in South Africa, and the capital of the Northern Cape. It is located near the confluence of the Vaal and Orange Rivers. The town has considerable historical significance due its diamond mining past and siege during the Second Boer War...
diamond fields in the 1870s. In 1874 surveyor Wells Hood, under the instruction of the railway engineer Thomas Brounger, found a potential route up the 2353 feet (717 m) climb from De Doorns in the Hex River valley to the top of the Little Karoo plateau east of the Valley, with gradient
Gradient
In vector calculus, the gradient of a scalar field is a vector field that points in the direction of the greatest rate of increase of the scalar field, and whose magnitude is the greatest rate of change....
s of no more than 1 in 40, very steep by railway standards. In addition, he proposed that a short tunnel
Tunnel
A tunnel is an underground passageway, completely enclosed except for openings for egress, commonly at each end.A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers...
would be required at the summit. Thomas Brounger's route through the Hex River Pass was selected by 1876, with the line to follow the route from Worcester
Worcester
The City of Worcester, commonly known as Worcester, , is a city and county town of Worcestershire in the West Midlands of England. Worcester is situated some southwest of Birmingham and north of Gloucester, and has an approximate population of 94,000 people. The River Severn runs through the...
through De Doorns
De Doorns
De Doorns, Western Cape is a settlement in Cape Winelands District Municipality in the Western Cape province of South Africa....
, up the pass via Osplaas, Tunnel and Matroosberg to Touws River
Touws River (town)
Touws River is a small railway town of 6,800 people in the Western Cape province of South Africa. It is located on the river of the same name, about north-east of Cape Town.-History:...
, Matjiesfontein
Matjiesfontein
Matjiesfontein is a settlement in Central Karoo District Municipality in the Western Cape province of South Africa....
, Laingsburg
Laingsburg, Western Cape
- History :Laingsburg was first established in the 1870s by Stephanus Greeff. He bought the farm Vischkuil-aan-de-Buffelsrivier . The town only started developing when the railway line to it was completed...
and on to Beaufort West
Beaufort West
Beaufort West is a town in the Western Cape province in South Africa. It is the largest town in the arid Great Karoo region, and forms part of the Beaufort West Local Municipality, with 37 000 inhabitants in 2001....
.
Cape Gauge
The standard gauge track of 4 feet 8½ inches could not be accommodated economically on the tight curves required by the Hex River Pass. This led to the decision by the Cape Government RailwaysCape Government Railways
The Cape Government Railways was the government-owned railway operator in the Cape Colony from 1874 until the creation of the South African Railways in 1910.-Private railways:...
(CGR) to abandon the use of Standard gauge
Standard gauge
The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...
, which had been used for the line between Cape Town
Cape Town
Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...
and Wellington
Wellington
Wellington is the capital city and third most populous urban area of New Zealand, although it is likely to have surpassed Christchurch due to the exodus following the Canterbury Earthquake. It is at the southwestern tip of the North Island, between Cook Strait and the Rimutaka Range...
, and to install the track across the pass at 3 in 6 in (1,066.8 mm) gauge. A subsequent decision resulted in all existing tracks of the CGR being converted to what was to become known worldwide as Cape gauge
Cape gauge
Cape gauge is a track gauge of between the inside of the rail heads and is classified as narrow gauge. It has installations of around .The gauge was first used by Norwegian engineer Carl Abraham Pihl and the first line was opened in 1862.- Nomenclature :...
.
Credit for the fact that most of the present day railway lines in Africa are Cape gauge can therefore be directly attributed to the Hex River Pass. Despite its quick and relatively cheap construction, the pass served the South African Railways for more than a century. It was the starting point of the country's first railway line to the Witwatersrand
Witwatersrand
The Witwatersrand is a low, sedimentary range of hills, at an elevation of 1700–1800 metres above sea-level, which runs in an east-west direction through Gauteng in South Africa. The word in Afrikaans means "the ridge of white waters". Geologically it is complex, but the principal formations...
and opened the way for Rhodes
Rhodes
Rhodes is an island in Greece, located in the eastern Aegean Sea. It is the largest of the Dodecanese islands in terms of both land area and population, with a population of 117,007, and also the island group's historical capital. Administratively the island forms a separate municipality within...
' colonisation
Colonisation
Colonization occurs whenever any one or more species populate an area. The term, which is derived from the Latin colere, "to inhabit, cultivate, frequent, practice, tend, guard, respect", originally related to humans. However, 19th century biogeographers dominated the term to describe the...
thrust into central Southern Africa
Southern Africa
Southern Africa is the southernmost region of the African continent, variably defined by geography or geopolitics. Within the region are numerous territories, including the Republic of South Africa ; nowadays, the simpler term South Africa is generally reserved for the country in English.-UN...
.
The original tunnel, Southern Africa’s first railway tunnel, is situated at Km 34 between De Doorns and Matroosberg. Just to the east of the tunnel was a siding, approriately named "Tunnel". The tunnel portals were of dressed stone masonry, but the inside was unlined. This tunnel served the railways for 53 years, until the track was relaid in 1929 to diminish a curve in order to accommodate larger locomotives. In the process a new concrete lined tunnel was sunk alongside the original. This latter tunnel remained in use for sixty years, until the line across the pass was closed in 1989.
First Bore
The restrictions on train length and the additional locomotive power required for the ascent eventually led to the decision to construct a tunnel system to eliminate the Hex River Pass altogether. The Hex River Tunnel scheme was initially started in 1945, but was abandoned three years later due to a lack of funds after the project encountered serious technical difficulties at the eastern portal of the longest of the four tunnels. The portal was dug immediately adjacent to the N1 national road some 15 kilometres (9 mi) west of Touws River and took the form of a gradient into a trench cutting, down to sufficient depth to commence tunneling.The bore was hardly more than about 66 feet (20 m) deep, however, when ground water flooding brought tunneling to a halt, and the project was eventually abandoned. Instead, the pass was electrified by 1954 and operated with Class 4E electric locomotives, which were amongst the most powerful electric locomotives in the world at that time.