George Massey Tunnel
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The George Massey Tunnel ( often referred to as Massey Tunnel) is a highway traffic tunnel in the Greater Vancouver region of southwestern British Columbia, Canada. It is located approximately 20 km (12 mi) south of the city centre of Vancouver, and approximately 30 km (20 mi) north of the Canada-U.S. Border at Blaine, Washington.
The tunnel was opened to traffic in March 1959 with a construction cost of approximately $25 million. It carries a four lane divided highway under the south arm of the Fraser River estuary, joining the city of Richmond to the north with the municipality of Delta to the south.
The tunnel forms part of Highway 99. It is named for (Nehamiah) George Massey, a former Member of the Legislative Assembly of British Columbia. He represented Delta between 1956 and 1960, and was a long-time advocate of a permanent crossing to replace an existing ferry that crossed the south arm of the Fraser River.
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[edit] Configuration
The tunnel is a single tube that is subdivided with a concrete wall, each side containing two traffic lanes. The typical traffic flow has two northbound lanes in the east tube and two southbound lanes in the west tube. In 1989 a counterflow system was introduced to meet increasing traffic demand in the tunnel.
At peak rush traffic periods, a reversible lane system is used, with series of movable barricades deployed reducing traffic in one direction to a single lane, while increasing the other direction to three lanes. Morning rush has three lanes northbound (inbound to Vancouver) and evening rush has three southbound lanes (outbound from Vancouver).
[edit] Construction and maintenance
The 629 m (2,063 ft) long tunnel is made up of six precast concrete sections (length: 105 m, 345 ft; height: 7 m, 23 ft; width: 23 m, 75 ft). These were floated into position by barge and then sunk into a shallow trench that had been dug into the loose sand and silt of the river bed. The trench and tunnel sections were then covered over with a protective layer of rock - 500 pounds of stone filled 50 feet (15 m) out on each side, plus a bed of 1,500 pound stone on top. A structure located at each end of the tunnel houses the main ventilation and pumping equipment. Concrete retaining walls make up the approaches, which extend out about 400 m (¼ mi) from the ventilation buildings. At its lowest point the roadway is about 25 m (80 ft) below sea level. (Note that the Fraser River flows into the Strait of Georgia about 5 km, 3 mi, downstream from the tunnel.) This was the first tunnel to use this construction method in North America.
Due to the tunnel being designed and constructed in the 1950s, very little consideration was given to seismic factors. The river bed is a 600 m (2,000 ft) thick layer of sediment on top of bedrock. This sedimentary layer may liquefy during a major earthquake,[1] [2] which would cause serious damage to the tunnel.[citation needed]
In recent years, as the awareness of the effect of serious seismic activity developed, an engineering assessment and subsequent retrofit project was initiated to increase the survivability of the tunnel in the event of a significant earthquake. This retrofit project started in the fall of 2004 and had been completed by the spring of 2006.
The tunnel was constructed for the British Columbia Toll Highways and Bridge Authority, and is now administered by the British Columbia Ministry of Transportation. It has not had a toll on it since the 1960s, when tolls were removed from all of the bridges and tunnels in the Lower Mainland (although tolls will be collected on the Golden Ears Bridge, targeted for completion in 2009 and the future twinned Port Mann bridge).
On February 16, 2006, it was reported that the provincial government had plans to expand the tunnel's capacity, from four lanes to six. This change is becoming increasingly necessary, as traffic jams occur frequently, especially if there is an accident inside the tunnel. The "H99" project is the name of the expansion.
This tunnel is also the only connection from South Delta to Richmond and Vancouver.
As the tunnel prohibits bicycles, fare-free shuttle service is available from April to October.
[edit] See also
[edit] External links
- Satellite photo of George Massey Tunnel from Google Maps
- BC Highways - Highway 99 - Pictures and diagrams of the Massey Tunnel
- Vancouver Sun Article - Twinned Tunnel Part of Victoria's Plan
- Buckand and Taylor Bridge Engineering, George Massey Tunnel project
- George Massey Tunnel Bicycle Shuttle
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