Science Fair Project Encyclopedia
Lions' Gate Bridge
The Lions' Gate Bridge is a suspension bridge that crosses the first narrows of Burrard Inlet and connects the City of Vancouver, British Columbia, to the North Shore municipalities of North Vancouver and West Vancouver. The bridge was completed in 1938 at a cost of $5,873,837.17. The total length of the bridge including the north viaduct is 1,823 metres (5,890 feet). The length including approach spans is 1,517.3 m (4,978 ft), the main span alone is 472 m (1,550 ft), and the tower height is 111 m (364 ft). The traffic volume on the bridge is 60,000 - 70,000 vehicles per day.
The bridge is a 3-lane bridge. The centre lane has traffic control signals on it and changes direction to accommodate the traffic patterns.
Starting in about 1890, bridge builders foresaw the possibility that a bridge across the first narrows would open up. There were a number who argued against the construction of the bridge, as many felt it would ruin Stanley Park, or cause problems for the busy seaport, or that it would take toll revenue away from the Second Narrows bridge. However, many also saw it as necessary in order to open up development on the North Shore and it was felt that these problems could be overcome. The decision decision was put to the electorate and 1927, the first plebiscite was defeated and the idea was put to rest for a short while.
James Towle Taylor , who had been part of this previous proposal and still owned the provincial franchise to build a bridge, had an opportunity to purchase large sections of property in North Vancouver and West Vancouver. He was able to interest the Guinness family (of beer fame), to invest in the land on the north shore of Burrard Inlet. They purchased 4,000 acres (16 km²) of West Vancouver mountainside through a syndicate called British Pacific Properties Ltd. This put momentum behind the construction of a bridge.
After considerable further negotiations with the Federal government approval was finally gained, with the requirement to use Vancouver materials and workmen as much as possible to provide employment during the depression.
The bridge was designed by the Montreal firm Monsarrat and Pratley .
The bridge was originally constructed as a 2-lane bridge, but when traffic increased, the road was repainted into 3 lanes. The third lane was originally used only for passing, but eventually lane control signage was added and it was used for traffic flow.
In 1975, the deteriorating north viaduct was replaced with a lighter, wider, and stronger steel deck, with wider lanes. This was done in sections using a series of short closures of the bridge; each time, one old section was lowered to the ground below and its replacement put into place.
In 1986 the Guinness family, as a gift to Vancouver, purchased decorative lights that make it a distinctive nighttime landmark.
In the 1990s, it was time for the bridge to be either significantly upgraded or replaced. A number of different proposals came forward including building a new bridge beside the existing bridge, building a tunnel from downtown to the north shore, or double decking the existing bridge. However, none of the proposals could overcome the City of Vancouvers objections to any increase in traffic into the downtown core and the provinces unwillingness to spend much money on the project. In the end the decision, was to upgrade the existing bridge, without adding any new lanes.
In 2000 and 2001, the main bridge deck was replaced. As with the earlier work, this was done with a series of separate closures to replace one section each time. The old section would be lowered to a barge below, and the new one raised into place and connected. The change allowed the two pedestrian walkways to be moved to the outside of the structure and the road lanes accordingly widened from 3 to 3.6 m (from 10 to 12 ft) each; the new sidewalks are also wider, 2.7 m (9 ft) each instead of 1.2 m (4 ft). Also, the main structural elements were moved to below the bridge deck, giving a much more open appearance.
The Lion's Gate Bridge has become a landmark of Vancouver and the North Shore.
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