West Gate Bridge

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West Gate Bridge
West Gate Bridge Melbourne.jpg
View of the bridge with a River Cruise Boat passing under
Official name West Gate Bridge
Carries 10 lanes (5 inbound, 5 outbound) (After expansion)
Crosses Yarra River
Locale Melbourne, Australia
Maintained by VicRoads
ID number WGB
Design Cable-stayed box girder
Total length 2,582.6 metres (8,473.1 ft)
Width Maximum of 37.3 metres (122.4 ft)
Longest span 336 metres (1,102 ft)
Clearance below 58 Metres (190.3 ft)
Opened 15 November 1978
Daily traffic 180,000
Connects the Melbourne CBD with south-western suburbs and Geelong West Gate Bridge GIF Aerial.gif
Coordinates 37°49′46″S 144°53′53″E / 37.82944°S 144.89806°E / -37.82944; 144.89806Coordinates: 37°49′46″S 144°53′53″E / 37.82944°S 144.89806°E / -37.82944; 144.89806
West Gate Bridge is located in Victoria
West Gate Bridge

The West Gate Bridge is a steel box girder cable-stayed bridge in Melbourne, Victoria, Australia. It spans the Yarra River, just north of its mouth into Port Phillip, and is a vital link between the inner city (CBD) and Melbourne's western suburbs; with the industrial suburbs in the west and with the city of Geelong, 80 kilometres (50 mi) to the south-west. It is one of the busiest road corridors in Australia.

The main river span is 336 metres (1,102 ft) in length, and the height above the water is 58 metres. The total length of the bridge is 2,582.6 metres (8,473.1 ft). It is the second longest in Australia behind the Houghton Highway and its twin the Ted Smout Memorial Bridge, and is twice as long as the Sydney Harbour Bridge. It is one of the highest bridges in Australia, most notably trailing that of the more iconic Sydney Harbour Bridge.

The bridge passes over Westgate Park, a large environmental and recreational reserve created during the bridge's construction. The bridge carries up to 200,000 vehicles per day.

Transportation[edit]

Motor vehicles[edit]

The West Gate Bridge carries five lanes of motor vehicle traffic in each direction, therefore a 10 lane dual-carriageway freeway bridge.

The freeway corridor (including the bridge itself) carries a very high volume and occupancy of traffic, between 180,000 - 200,000 cars / trucks / motorcycles use it per day, according to VicRoads. This makes the West Gate Bridge and West Gate Freeway one of the busiest road corridors in Australia.

However, being the only main direct link between Melbourne's CBD and the West, it is frequently congested during the morning and afternoon peaks (despite having 5 lanes in each direction) and is constantly busy 24/7, due to the amount and type of vehicles coming in and out of Melbourne (i.e.) Port of Melbourne.

The bridge was originally tolled. Tolls were abolished in 1985, because drivers were using other routes to avoid the toll.[1]

Cycling and the Westgate[edit]

Cyclists are prohibited from using the bridge except for special bicycle events, notably the MS Summer cycle, which is a fundraising event for multiple sclerosis, and the Around the bay in a day Bicycle Network [2] event that raises money for The Smith Family charity. The Westgate Punt is a foot ferry that runs directly below the bridge, taking cyclists and pedestrians across the Yarra between a jetty at Fishermans Bend near Westgate ParkBay Trail and a jetty adjacent to Scienceworks MuseumHobsons Bay Coastal Trail. It operates on demand, from Monday to Friday in morning and evening peaks, and on weekends and public holidays from 10:00 am to 5:00 pm.

Being a freeway, the West Gate Freeway / West Gate Bridge have signs on each on-ramp and on every other on-ramp for 'Urban Freeways' across Melbourne, stating that cyclists are prohibited to enter such roads (especially on the West Gate Bridge where it would incur the most dangerous conditions).

Every freeway on-ramp in Victoria has regulatory signs, a white coloured sign stating 'NO Pedestrians; Bicycles; Animals; Agricultural Machinery ... Permitted on this freeway at any time except with authority'. Then a smaller green sign below states 'Freeway Entrance' or 'Start Freeway'.

History[edit]

Collapse[edit]

2010 ABC report on the collapse.

Two years into construction of the bridge, at 11.50 am on 15 October 1970, the 112 m (367.5 ft) span between piers 10 and 11 collapsed and fell 50 m (164 ft) to the ground and water below. Thirty-five construction workers were killed. Many of those who perished were on lunch break beneath the structure in workers' huts, which were crushed by the falling span. Others were working on and inside the girder when it fell. The whole 2,000-tonne mass plummeted into the Yarra River mud with an explosion of gas, dust and mangled metal that shook buildings hundreds of metres away. Nearby houses were spattered with flying mud. The roar of the impact, the explosion, and the fire that followed, could be clearly heard over 20 kilometres (12 mi) away. A West Gate Bridge Memorial to workers who lost their lives is located near the bridge. On the following morning, 16 October, Sir Henry Bolte (Premier of Victoria) announced that a Royal Commission would be set up immediately to look into the cause of the disaster. The Prime Minister, John Gorton, said: "I am sure the whole of Australia is shocked and saddened by the serious accident at West Gate Bridge. Please extend my deepest sympathy to all those families to whom this tragic event has brought such grief."[3]

Cause[edit]

The West Gate Bridge as seen from the walkway near the West Gate Bridge Memorial Park

A Royal Commission into the collapse was established, which concluded on 14 July 1971. It attributed the failure of the bridge to two causes: the structural design by designers Freeman Fox & Partners and an unusual method of construction by World Services and Construction, the original contractors of the project.

On the day of the collapse, there was a difference in camber of 11.4 centimetres (4.5 in) between two half-girders at the west end of the span which needed to be joined. It was proposed that the higher one be weighted down with 10 concrete blocks, each 8 tonnes (11 t), which were located on site. The weight of these blocks caused the span to buckle, which was a sign of structural failure. The longitudinal joining of the half girders was partially complete when orders came through to remove the buckle. As the bolts were removed, the bridge snapped back and the span collapsed.

Six twisted fragments of the collapsed bridge can be found adorning the gardens in the engineering faculty of Monash University, Clayton campus. It is said by students that they are to remind engineers of the consequences of their errors. Monash University acquired these when asked to participate in the investigation of the collapse.

Completion[edit]

Construction resumed in 1972, with the bridge being completed in 1978. After 10 years of construction, the bridge, a part of the larger West Gate Freeway, cost $202 million.[1]

In 2004 speed cameras were erected on the bridge, but were not activated until September 2005, because of issues with a similar camera on the Western Ring Road.[4] However these speed cameras were switched off in 2005, and currently remain disabled, as the sway of the bridge prevents secondary verification of the alleged speed against a fixed point.[5] In 2006 the State Government spent $1.3 million on erecting railway style boom barriers at each entrance to the bridge to block traffic in the event of a terrorist attack.[6] In March 2007 the State Government announced that two flagpoles would be erected atop the main bridge pylons, to fly the Australian and Victorian flags, each being 10 metres by 5 metres in size and 135m above sea level.[7] Costing $350,000 to install and $15,000 a year to maintain,[8] the flags were unfurled on 24 September 2008.[9]

On 5 August 2007 it was reported that the Victorian Government was planning a $240 million project to identify and eliminate structural weaknesses in the bridge, with specific concerns including crash barriers, cracking, corrosion and potential buckling. News of the work was prompted by the collapse of the I-35W Mississippi River bridge in Minneapolis, Minnesota, United States. Experts were reported as saying the West Gate was initially designed to carry loads of 25 tonnes but now carried B-double trucks weighing up to 68 tonnes. The bridge was built to carry 40,000 vehicles a day, but volumes are now more than four times the original amount, approximately 160,000 vehicles on an average day.[10]

Expansion[edit]

On 17 May 2006, the State Government as part of their Meeting Our Transport Challenges plan announced plans to change traffic flow in peak periods on the West Gate Bridge and approaches to it, using a reversible lane to provide five traffic lanes in the peak direction, opposing traffic having three lanes.[11] This was to be done using overhead signals and barriers and the State Government allocated funds to this project in its 2006–2007 state budget,[citation needed] but the works were never carried out.

In 2008 the expansion plans were revised as part of the Victorian Transport Plan, when it was announced that the bridge would be widened to 5 lanes in each direction, the space being gained by narrowing the existing traffic lanes and closing the emergency lanes, in a move criticised by Victorian fire, police and ambulance unions.[12] Overhead gantries would be used to direct traffic out of lanes when breakdowns and accidents occur. Costed at $240 million, each lane would be 3.1 metres wide, by comparison lanes on the Sydney Harbour Bridge have a width of 2.8 metres.[12] Roads Minister Tim Pallas claimed that the plan would allow the bridge to carry 50 percent more vehicles, while reducing crashes by 20 percent.[13] Structural analysis work on the bridge concluded in early 2009 and was completed over a 14-month period. Works to strengthen the bridge commenced in the first half of 2009, with the entire strengthening project scheduled for completion in 2011.[14]

On 22 June 2011 all five lanes were finally opened to the public in both directions, with the completion of the required strengthening works.[15] The full cost was $347 million, $107 million more than VicRoads had originally planned, but included considerable additional scope of works. This cost increase was after the deletion of $20 million architectural lighting originally included in the scope of the works.[15] The engineers for the strengthening project, Flint & Neill and Sinclair Knight Merz, won the 2012 Institution of Structural Engineers Supreme Award for structural engineering for the project.[16]

West Gate Bridge Flag[edit]

On 11 March 2014 an artist flag was raised on the West Gate Bridge as part of Melbourne Now, ‘Flags for Melbourne’. The flag is a collaborative design between four contributing artists involved in the show who shared an affinity with the bridge. It’s a reference to 1803 maritime communications by Rear Admiral Popham, the symbol on the flag meaning ‘I can spare what you asked for’. The new flag over the west side of the West Gate Bridge will be flying until the end of the Melbourne Now show on 25 March. Artists Brook Andrew, Helen Johnson, Kate Daw and Jon Campbell were collaborating with Stewart Russell as curator.

Future[edit]

The West Gate Bridge at sunset, with Docklands Stadium in the foreground.

Strong growth in suburbs along the route, and increased freight through the Port of Melbourne, means that the corridor is experiencing traffic congestion during peak periods, is vulnerable to short term interruptions and is rapidly approaching capacity. Proposals to abate congestion by allowing more traffic have included bridge widening, a tunnel underneath the river, or adding a second deck to the bridge. Many such plans have come under fire from community groups such as the Public Transport Users Association and Environment Victoria advocating investment in alternative forms of transport.

A private sector report made public in February 2006 suggested building a companion tunnel to the West Gate Bridge under the Yarra River. Made up of three separate bores to carry traffic in either direction and a freight rail line, the portals would have been north of Williamstown Road in Port Melbourne, and between Blackshaws and Melbourne roads in Altona North.[17][18]

The State Government also assessed options for the development of another east-west link in 2008. Sir Rod Eddington, former CEO of British Airways and Chairman of the Victorian Major Events Company, will head the assessment of the future East-West connections and recommend the best way forward for public transport, road and freight travel for the entire Monash-West Gate corridor. By December 2008 the State Government announced it was planning for such a link, anticipated to be a three kilometre road tunnel under Footscray and the Maribyrnong River. Linking Dynon and Footscray Roads in the Port of Melbourne precinct to Geelong Road in West Footscray, now known as the East-West road connection its cost is estimated at more than $2.5 billion.[19]

Also in consideration is the expansion of the bridge to facilitate rail traffic including freight, metro and tram services.

Suicide location[edit]

Police data show up to one suicide happens every three weeks at the West Gate Bridge. A 2004 coroner's report recommended anti-suicide fencing or barriers be erected on the bridge to deter people from taking their lives.[20] In 2008, the bodies of a mother in her late 20s and her 18-month-old baby were found on the river bank below the West Gate Bridge, prompting further calls to erect a suicide barrier.[21]

Those who argue for a suicide barrier claim that most of those who jump from the West Gate Bridge do so through impulse and that police officers who try to save those who try to jump are putting their own lives in danger. There are multiple incidents of police officers dangling off the side of the bridge while holding onto would-be jumpers.[22] A 2000 Royal Melbourne Hospital study on people who jumped from the bridge found at least 62 cases between 1991 and 1998. Seven people survived the 58-metre fall. Seventy-four percent of those who jumped from the bridge were male, with an average age of 33. More than 70 percent were suffering from mental illness.[23] Of those who jumped off the West Gate Bridge, 31 percent fell on land. Some of those who landed in water drowned afterwards.[24]

In 2009 a Melbourne girl, Darcey Freeman, aged 4, was thrown off of the bridge by her father and later died in hospital. In April 2011, Arthur Freeman was found guilty of murder and sentenced to life in prison.[25]

In February 2009, the first stage of a temporary suicide barrier was erected, constructed of concrete crash barriers topped with a welded mesh fence. By June that year, it has been claimed that the fence has prevented two suicides.[26] The permanent barrier has now been completed throughout the span of the bridge. The barriers are costed at $20 million.[12]

See also[edit]

[1]

References[edit]

  1. ^ a b M. G. Lay and K. F. Daley (July 2002). "The Melbourne City Link Project". Transport Policy 9 (3). sciencedirect.com. Retrieved 17 July 2008. 
  2. ^ https://www.bicyclenetwork.com.au/
  3. ^ 'West Gate', Bill Hitchings, 1979, Outback Press
  4. ^ Ashley Gardiner (21 September 2005). "Bridge cameras set to bring in millions". Herald Sun (Australia). 
  5. ^ Matthew Shulz (22 May 2008). "Malfunctioning West Gate Bridge speed cameras turned off". Herald Sun (Australia). 
  6. ^ Tanya Giles (18 January 200). "West Gate boom gates to fight terror". Herald Sun (Australia). Retrieved 25 September 2008.  [dead link]
  7. ^ "FLAGS TO FLY ON THE WEST GATE BRIDGE". Media Release: OFFICE OF THE PREMIER. legislation.vic.gov.au. 13 March 2007. Retrieved 25 September 2008. 
  8. ^ Lucas, Clay; Dowling, Jason (17 September 2008). "Pride in the flags to cost $350,000". The Age (Melbourne). Retrieved 25 September 2008. 
  9. ^ Ashley Gardiner (25 September 2008). "West Gate Bridge shows flag colours". Herald Sun (Australia). Retrieved 25 September 2008. [dead link]
  10. ^ Paul Heinrichs (5 August 2007). "$240m West Gate facelift to bridge safety fears". The Age (Melbourne). Retrieved 18 June 2009. 
  11. ^ State of Victoria (May 2006). Meeting Our Transport Challenges (Report).
  12. ^ a b c Clay Lucas (5 December 2008). "Police, ambulance unions criticise move to close West Gate emergency lanes". The Age (Melbourne). Retrieved 18 June 2009. 
  13. ^ "No emergency on West Gate Bridge". ABC News. Australia: ABC. 4 December 2008. Retrieved 18 June 2009. 
  14. ^ "West Gate Bridge Strengthening". Monash-CityLink-West Gate upgrade. mcwupgrade.com.au. Retrieved 18 June 2009. 
  15. ^ a b Clay Lucas (23 June 2011). "Costs head north as another lane goes west". The Age. Australia. Retrieved 27 June 2011. 
  16. ^ IStructE. "2012 IStructE Supreme Award Winners". UK. Retrieved 12 December 2012. 
  17. ^ Australian Associated Press (6 February 2006). "$2bn tunnel plan for West Gate Bridge". The Age (Melbourne). Retrieved 18 June 2009. 
  18. ^ John Ferguson and Geraldine Mitchell (18 February 2008). "Traffic on Melbourne's West Gate Bridge slows under heavy load". Herald Sun (Australia: news.com.au). Retrieved 18 June 2009. 
  19. ^ "West Gate Bridge Alternative". Victorian Transport Plan. www4.transport.vic.gov.au. December 2008. Retrieved 18 June 2009. [dead link]
  20. ^ Mark Dunn and Anthony Dowsley (14 June 2008). "Anti-suicide barrier urged for West Gate Bridge". Herald Sun (Australia: news.com.au). Retrieved 18 June 2009. 
  21. ^ Mark Dunn and Antonia Magee (5 June 2008). "Mum and baby dead in 'gut-wrenching' tragedy". Herald Sun (Australia: news.com.au). Retrieved 18 June 2009. [dead link]
  22. ^ Mark Dunn (9 November 2006). "Police risk lives on death bridge". Herald Sun (Australia: news.com.au). Retrieved 18 June 2009. 
  23. ^ Karen Poh (10 June 2008). "Fence on bridge". Star News Group. starnewsgroup.com.au. Retrieved 18 June 2009. 
  24. ^ Coman M, Meyer AD, Cameron PA (2000). "Jumping from the Westgate Bridge, Melbourne". The Medical Journal of Australia (ncbi.nlm.nih.gov) 172 (2): 67–9. PMID 10738475. 
  25. ^ Thomas Hunter (11 April 2011). "West Gate father sentenced to life in prison". The Age (Australia: www.theage.com.au). Retrieved 7 June 2012. 
  26. ^ Mark Dunn (18 June 2009). "West Gate Bridge fence a live saver". Herald Sun (Australia: news.com.au). Retrieved 18 June 2009. [dead link]

External links[edit]