49-539: Meldon Viaduct is a disused railway viaduct crossing the West Okement River at Meldon , 2.5 miles (4.0 km) south-west of Okehampton , on the edge of Dartmoor in Devon , South West England. This truss bridge was constructed from wrought iron , instead of stone or brick arches. It opened in 1874 for a single track; in 1879 its width was doubled for a second track. Although regular services were withdrawn in 1968,
98-522: A scheduled monument , and is owned by Meldon Viaduct Company Ltd, a charitable company set up in 1998 to safeguard it. At various times since the closure of the line, local people and enthusiasts have campaigned for its re-opening, a campaign which gained added prominence in 2014 after severe winter storms severed the Great Western Main Line at Dawlish in February. According to Network Rail ,
147-490: A half times the amount of rainfall that they would normally expect. The flood phenomena ranged from coastal flooding , pluvial flooding, fluvial flooding to groundwater flooding. The flooding took over most of the Somerset Levels and saw the main railway line to Cornwall and West Devon at Dawlish severed for several weeks. A series of low pressure areas developed or formed over North America explosively deepening over
196-543: A landscape, usually by bridging a river valley or other eroded opening in an otherwise flat area. Often such valleys had roads descending either side (with a small bridge over the river, where necessary) that become inadequate for the traffic load, necessitating a viaduct for "through" traffic. Such bridges also lend themselves for use by rail traffic, which requires straighter and flatter routes. Some viaducts have more than one deck, such that one deck has vehicular traffic and another deck carries rail traffic. One example of this
245-641: A real pounding from the sea". In a press release, First Great Western had initially said the line would only be closed until Wednesday as a result of the "poor weather conditions", but this was extended the until the end of the week. High tides lashed Plymouth's Hoe seafront and the nearby Barbican. Near Exeter, firefighters rescued a man from a vehicle stuck in floodwater. Sea defences, walls and footpaths were damaged, including at Newlyn Green on 4 February. The Tamar Bridge between Plymouth in Devon and Saltash in Cornwall
294-595: A repurposed rail viaduct provides a garden promenade on top and workspace for artisans below. The garden promenade is called the Coulée verte René-Dumont while the workspaces in the arches below are the Viaduc des Arts . The project was inaugurated in 1993. Manhattan's High Line , inaugurated in 2009, also uses an elevated train line as a linear urban park . In Indonesia viaducts are used for railways in Java and also for highways such as
343-450: A route from Exeter that would have to skirt around the north and west sides of Dartmoor. Meldon Viaduct was begun in 1871, and opened on 12 October 1874, linking Okehampton and Lydford (Lidford). It was part of the LSWR's routes to Plymouth (from 1876) and Bude (from 1898) via Okehampton. Originally it carried a single track, but it was doubled in 1879 when a second viaduct of similar design
392-422: Is 535 ft (163 m) long, standing 151 ft (46 m) above the bottom of the valley. It has a slight curve which, combined with its exposed position, resulted in speed and weight restrictions being applied to trains crossing it. The speed limit was set at 20 mph (32 km/h) in 1927. In 1938 braces were added between the lower ends of the older trestles. In 1944, to allow heavy wartime traffic,
441-617: Is a 19th-century derivation from an analogy with ancient Roman aqueducts . Like the Roman aqueducts , many early viaducts comprised a series of arches of roughly equal length. The longest viaduct in antiquity may have been the Pont Serme which crossed wide marshes in southern France. At its longest point, it measured 2,679 meters with a width of 22 meters. Viaducts are commonly used in many cities that are railroad hubs , such as Chicago, Birmingham, London and Manchester . These viaducts cross
490-500: Is built across land rather than water, the space below the arches may be used for businesses such as car parking, vehicle repairs, light industry, bars and nightclubs. In the United Kingdom, many railway lines in urban areas have been constructed on viaducts, and so the infrastructure owner Network Rail has an extensive property portfolio in arches under viaducts. In Berlin the space under the arches of elevated subway lines ( S-Bahn )
539-455: Is made of a varying number of sections, end-to-end, each consisting of six flanged curved pieces riveted together side-by-side. The trestles taper inwards from the bottom, and rest on 24 ft (7.3 m) wide masonry bases, the newer trestles straddling the older ones at the bottom. At each end of the viaduct, the trusses are supported on cast-iron sliding bearings on four cast-iron cylinders filled with concrete, which are deeply embedded in
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#1732869061707588-883: Is the Prince Edward Viaduct in Toronto, Canada, that carries motor traffic on the top deck as Bloor Street , and metro as the Bloor-Danforth subway line on the lower deck, over the steep Don River valley . Others were built to span settled areas, crossing over roads beneath—the reason for many viaducts in London. Viaducts over water make use of islands or successive arches. They are often combined with other types of bridges or tunnels to cross navigable waters as viaduct sections, while less expensive to design and build than tunnels or bridges with larger spans, typically lack sufficient horizontal and vertical clearance for large ships. See
637-570: Is the lead on managing fluvial flood risk...The EA owns and operates a sluice gate which controls flow from River Colne to the River Ash. This...is designed to ensure there is always a base flow in the River Ash to maintain the ecosystem of the river. This sluice gate adjusts automatically to send flow into the River Ash as needed. In the February event the EA overrode the automatic settings on this gate to control flooding. On 9 February (morning), EA reported that
686-407: Is used for several different purposes, including small eateries or bars. Elevated expressways were built in major cities such as Boston ( Central Artery ), Los Angeles, San Francisco, Seoul , Tokyo and Toronto ( Gardiner Expressway ). Some were demolished because they were unappealing and divided the city. In other cases, viaducts were demolished because they were structurally unsafe, such as
735-526: The Chesapeake Bay Bridge-Tunnel . The Millau Viaduct is a cable-stayed road-bridge that spans the valley of the river Tarn near Millau in southern France. It opened in 2004 and is the tallest vehicular bridge in the world, with one pier's summit at 343 metres (1,125 ft). The viaduct Danyang–Kunshan Grand Bridge in China was the longest bridge in the world as of 2011 . Where a viaduct
784-629: The Embarcadero Freeway in San Francisco, which was damaged by an earthquake in 1989. However, in developing nations such as Thailand ( Bang Na Expressway , the world's longest road bridge ), India ( Delhi-Gurgaon Expressway ), China, Bangladesh, Pakistan, and Nicaragua, elevated expressways have been built and more are under construction to improve traffic flow, particularly as a workaround of land shortage when built atop surface roads. Other uses have been found for some viaducts. In Paris, France,
833-760: The Jakarta Inner Ring Road . In January 2019, the Alaskan Way Viaduct in Seattle was closed and replaced with a tunnel after several decades of use because it was seismically unsafe. 2013%E2%80%9314 United Kingdom winter floods The 2013–2014 United Kingdom winter floods saw areas of the United Kingdom inundated following severe storms . The south of England saw heavy rainfalls associated with these storms which caused widespread flooding, power cuts and major disruptions to transport. Economically,
882-537: The River Severn were similar in magnitude to those experienced during the 2007 United Kingdom floods . The 2012 Great Britain and Ireland floods had brought severe flooding to the Somerset Levels . During December 2013 and January 2014 heavy rainfall led to extensive flooding on the Somerset Levels with over 600 houses and 17,000 acres (6,900 ha) of agricultural land, including North Moor , Curry and Hay Moors and Greylake , affected. The village of Thorney
931-521: The Staines Aqueduct owned by Thames Water which briefly burst its banks. The latter said it had been following an existing three-party protocol. The EA replaced its inadequate sluice quickly. The Council's resultant section 19 Report was published on 20 April 2015. It states "the primary source of flooding that contributed to this flooding incident was fluvial in nature; the Environment Agency
980-451: The 23–27 December 2013 brought heavy rainfall to southern England, especially in a swathe from Dorset through Hampshire, Surrey and Kent. The first storm brought travel disruptions, especially as the flooding affecting Yalding and the electrical substations at Gatwick Airport leaving the northern terminal without power on Christmas Eve. After Cyclone Dirk on Christmas Day, saturated ground led to localised flooding in southern England, as
1029-711: The Atlantic over Scotland and the North Sea inducing a storm surge in the Irish Sea and North Sea coasts of the United Kingdom. In the North Sea some of the highest level tides were recorded in the Humber and Thames estuaries, exceeding levels which occurred during the disastrous North Sea flood of 1953 . Flooding occurred in Tyneside , Teesside , along the Yorkshire coast, around the Humber and
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#17328690617071078-584: The Atlantic/gulf stream before reaching the European coast. An Omega Block developed over northern Norway/Scandinavia which prevented the lows moving east over Europe, with a series of lows "dying" to the northwest of the British Isles. The blocking pattern over northern Norway led to a severe drought and forest fires there in early 2014. The period began on 5 December 2013 when a deep low pressure area moved from
1127-593: The Hythe End intake gates to the Aqueduct were fully closed. And that from this point, the Aqueduct was being fed solely with floodwater originating from the County Ditch and Wraysbury River. Thames Water increased the pumping rate from 270 million litres-a-day to 350 million litres-a-day from its Birch Green pumping station in an attempt to control flood levels. On 9 February, according to the EA, they asked Thames Water to close
1176-483: The Moor Lane sluice gate, which is located on the Aqueduct. Thames Water claimed to have no record of receiving that request and as a consequence, the gate was not closed... ...the Aqueduct had partially collapsed while causing significant damage. LLFA Surrey County Council had no direct flood risk management functions during the event. [M]odelling work due...by the EA...will inform more robust water management measures in
1225-568: The Wash , where in particular the town of Boston, Lincolnshire was badly affected by when the high tide overtopped defences. Coastal flooding particularly affected the south and west of the UK, with severe damage reported in Wales, Cornwall, Devon and Dorset. A particularly notable event occurred on 5 February when the seawall and railway line were breached at Dawlish. The only railway that runs south-west of Exeter
1274-457: The ballast quarry at Meldon. In 1970, a road was built across the viaduct to permit lorries access to the Meldon Dam construction site. The bridge was assessed in 1990 as being too weak to carry trains and the rails were removed. Six years later, the viaduct was refurbished and re-opened as part of the 11 mi (18 km) Granite Way , a combined cycle and foot path (part of NCR27 ). It is now
1323-588: The beginning of December until the end of February, was the wettest recorded in the UK since records began in 1766. Parts of South East England received almost two and a half times the amount of rainfall that they would normally expect. For two days in February, the River Ash flooded at least 80 homes, their grounds, garages and/or outbuildings in Staines-upon-Thames . Slow flow into the swollen Thames created flooding pinchpoints of two Colne distributaries into
1372-529: The bridge was used for shunting by a local quarry. In the 1990s the remaining single track was removed. The crossing is now used by the Granite Way , a cycle track skirting Dartmoor. It is a scheduled monument , and is one of only two surviving railway bridges in the United Kingdom that use wrought iron lattice piers to support wrought iron trusses. In the 19th century, the London and South Western Railway (LSWR)
1421-503: The condition of Meldon Viaduct was a significant obstacle to the re-opening of the line, and it would need to be replaced before trains could run on the line. The viaduct is constructed mainly of wrought iron . It is one of two surviving wrought iron truss and trestle railway bridges in the United Kingdom, the other being the Bennerley Viaduct , between Nottinghamshire and Derbyshire, which differs by having lattice trusses (meaning
1470-470: The diagonals are criss-crossed). The structure is actually two viaducts side-by-side. Each viaduct consists of six spans of 90 ft (27 m), bridged by a pair of Warren trusses at 5 ft (1.5 m) centres, which are supported by five lattice trestles . When the original viaduct was widened to allow double-track operation, a second viaduct of almost identical construction was erected on its south-east side, 7 ft 6 in (2.29 m) from
1519-827: The estimation of homes internally flooded, in total, across its other parts (eight districts) less acutely affected than its Thames Valley three districts. The flooding in the three north-west Boroughs of Surrey was predominately due to the Thames. It was caused by unprecedented rainfall during the winter 2013/2014 period (275% in Surrey compared with an average winter). There were approximately 1170 incidents of internal property flooding in Runnymede during winter 2013/2014; approximately 130 in Spelthorne; and about 100 in Elmbridge. The Thames's peak flow
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1568-535: The flooding. Prince Charles and several senior politicians visited the area. Controversy arose about the role of the Environment Agency , with claims that the need for ongoing dredging of the main rivers had been neglected. However, Professor of Water Management at Cardiff University, and other hydrologists made clear that dredging does not offer a useful solution to flooding on the Levels. A stormy period from
1617-503: The future. The army dispensed free sandbags to Wraysbury victims. In Datchet, Princes William and Harry helped with defences at a road including a school which then closed for months. The Thames Barrier was used on an unprecedented level during this period. The operational use of the gates that are designed to prevent London flooding, span the River Thames between Silvertown and Charlton , quadrupled and accounted for nearly half of
1666-512: The ground. Viaduct A viaduct is a specific type of bridge that consists of a series of arches, piers or columns supporting a long elevated railway or road. Typically a viaduct connects two points of roughly equal elevation, allowing direct overpass across a wide valley, road, river, or other low-lying terrain features and obstacles. The term viaduct is derived from the Latin via meaning "road", and ducere meaning "to lead". It
1715-498: The large railroad yards that are needed for freight trains there, and also cross the multi-track railroad lines that are needed for heavy rail traffic. These viaducts provide grade separation and keep highway and city street traffic from having to be continually interrupted by the train traffic. Likewise, some viaducts carry railroads over large valleys, or they carry railroads over cities with many cross-streets and avenues. Many viaducts over land connect points of similar height in
1764-470: The original one, with the gap spanned by bracing and timber decking. The new viaduct then carried the down line (from London). The trusses are 9 ft 4 in (2.84 m) high. The bottom (tension) members of each newer truss include a continuous plate underneath for extra strength. The trestles vary in height from 48 ft (15 m) to 120 ft (37 m); each is constructed of four columns connected by horizontal and diagonal bracing. Each column
1813-437: The outer trestle legs were weighted with additional concrete to resist uplift. The viaduct was further strengthened from 1959–1960, with the inner trestle legs being weighted, and the bracing of the original trestles being replaced with stronger members. Passenger services on the line were withdrawn in 1968, after which the line reverted to a single track and the viaduct was used predominantly for shunting freight trains serving
1862-458: The storm brought up to 60mm of rain to the UK. A major incident was declared including parts of Leatherhead and Dorking ; Fire Brigade unions calling off a planned strike for the counties. An Environment Agency spokesman said flooding in Kent and Sussex was the worst since Autumn 2000 . Surrey County Council produced statutory investigation reports, documenting responsibilities, actions, next steps and
1911-517: The worst affected areas were Somerset , Devon , Dorset and Cornwall in the south west and the Thames Valley in the south east. The Met Office reported the storms produced the wettest 1 December to 31 January since 1876; a local authority report states the winter as a whole, from the beginning of December until the end of February, was the wettest recorded in the UK since records began in 1766. Parts of South East England received almost two and
1960-615: Was "a disaster" and called on the Transport Secretary to intervene. A landslip on the West of England Main Line at Crewkerne led to Somerset cutting off Exeter's railways (apart from the Tarka Line to Barnstaple in its county) on 8 February. Repairs were initially expected to take a week, but an inspection found the track was safe for slow moving trains. The line re-opened and a limited service
2009-470: Was abandoned and Muchelney cut off. Northmoor Green , which is more commonly known as Moorland was also severely affected. It was said that the government had not been quick enough to react and provide assistance to flooded communities. Flood relief activities included the use of rescue boats and the army. High volume pumps were brought in from the Netherlands and installed at several points to try to relieve
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2058-557: Was assessed as having a 1 in 15–20 annual chance Shepperton . Many residents in Wraysbury and Datchet berated the bank-damaging flows admitted into the Jubilee River , an anabranch for Windsor and Maidenhead . They blamed this sluice-controlled flow for augmenting the Thames which caused them flooding. A Surrey County Council investigation report states the winter as a whole, from
2107-511: Was closed to all traffic for a period after wind speeds surpassed 70 mph (110 km/h). It was reckoned that the storms had caused more than £4m worth of damage across Cornwall in a month. David Cameron chaired his first COBRA meeting of the year and announced an extra £100m for flood works on 5 February. Meanwhile, powerful waves continued to thrash the exposed coastline railway line at Dawlish and slightly damaged Dawlish station itself. A wave measuring more than 70 ft (21 m)
2156-432: Was constructed next to it and the two were joined. This was done while the original track remained open. To obviate high scaffolding, the trestles were erected by derricks mounted on the original structure. The 12 trusses, each weighing 21 long tons, were constructed nearby and lifted by two heavily-ballasted, rail-mounted cranes, which were then pulled onto the original bridge, and the truss lowered into position. Each truss
2205-588: Was in competition with the Great Western Railway (GWR) to provide passenger trains from London to Devon and Cornwall . But the South Devon Railway , an associate of the GWR, had already built a line from Exeter St Davids to Plymouth along the south coast and the south side of Dartmoor, under the direction of Isambard Kingdom Brunel . Thus the LSWR, and its engineer, William Galbraith , were left with
2254-413: Was installed in about 2 hours 30 minutes, thus the work could be arranged around the railway timetable without closing the line. The method, devised by engineer T. Wrightson and supervised on site by W. Jacomb, worked well, and the entire ironwork was erected in 16 weeks. On 5 May 1931 a carpenter, F. Rook, was killed in an accident while replacing timber decking on the down line. The viaduct
2303-409: Was recorded off the coast of Penzance. A flood buoy nearby triggered a reading of 74.8 ft (22.8 m) at 3 am. A Department for Transport source said that the "most pressing issue" was to get the line up and running as soon as possible, "but equally it is clear it is important we look at the long term as well." Lib Dem MP for Torbay , Adrian Sanders , said the loss of the main line
2352-516: Was restored on 9 February after signalling problems were resolved. The alternative route along the Bristol to Exeter line was flooded on the Somerset Levels for longer. The number of properties flooded was less than in the 2007 United Kingdom floods and was akin to the Autumn 2000 western Europe floods . During this flood more than 200,000 sandbags were used. Flooding on the middle and lower reaches of
2401-499: Was severed on 3 February when a 165 ft (50 m) section of the Riviera Line track was damaged at Dawlish . Network Rail said it had pulled all repair staff away from working on washed away track on 4 February. A section of the town's sea wall was later reported to have washed away among with the track. A Network Rail spokesman estimated "hundreds of tonnes" of ballast had been dislodged from under tracks after they had "taken
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