Dunsmuir Tunnel

The Dunsmuir Tunnel is a subway tunnel below Dunsmuir Street in Vancouver, British Columbia, Canada. The tunnel is used by the Expo Line of Metro Vancouver's SkyTrain rapid transit system. It is located downtown and has Burrard and Granville stations built within the tunnel. The western tunnel portal is located midway between Waterfront and Burrard stations, while the eastern portal is adjacent to Stadium–Chinatown station.

Dunsmuir Tunnel
Westbound SkyTrain platform at Granville station
Overview
LocationVancouver, British Columbia
Coordinates49.282981°N 123.115420°W / 49.282981; -123.115420
StartWaterfront
EndStadium–Chinatown
No. of stations2
Operation
Work begun1931
OpenedJuly 16, 1933 (1933-07-16)
ReopenedDecember 11, 1985 (1985-12-11)
OwnerTransLink
TrafficAutomated guideway transit
Technical
Length1,396 metres (4,580 ft)
No. of tracks2
ElectrifiedThird rail

History

The former eastern portal used by the Canadian Pacific Railway

The tunnel was originally built by the Northern Construction Company in 1932 connecting the Canadian Pacific Railway railyards on Burrard Inlet and False Creek at a cost of $1.6 million. The tunnel's original east portal was located further south than the current portal, easing trains into the False Creek yards on a gentle southward curve. It was clearly visible until about 2005, where it was almost completely hidden next to an outdoor storage area behind the Costco. The original portal was destroyed in 2011 to make way for a new development, but there remains an abandoned section of tunnel, unused by SkyTrain.[1][2][3]

The tunnel was taken over by BC Transit in the early 1980s when the SkyTrain system was built in conjunction with Expo 86. Because the tunnel is only wide enough to accommodate a single railway track but with sufficiently high clearance, a superstructure was built inside the tunnel to carry the westbound SkyTrain track above the eastbound track. This results in the two stations within the tunnel having a split platform configuration.

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gollark: osmarksISA™️-2028 is a VLIW stack machine. Specifically, it executes a 384-bit instruction composed of 8 48-bit operations in parallel. There are 8 stacks, for safety. Each stack also has an associated base memory address register, which is used in some "addressing modes". Each stack holds 64-bit integers; popping/peeking an empty stack simply returns 0, and the stacks can hold at most 32 items. Exceeding a stack's capacity is runtime undefined behaviour. The operation encoding is: `AABBBCCCCCCCCC`:A = 2-bit conditional operation mode - 0 is "run unconditionally", 1 is "run if top value on stack is 0", 2 is "run if not 0", 3 is "run if first bit is ~~negative~~ 1".B = 3-bit index for the stack to use for the conditional.C = 9-bit opcode (for extensibility).
gollark: By "really fast", I mean "in a few decaminutes, probably".
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See also

References

  1. "The SkyTrain Tunnel - The History of Metropolitan Vancouver". vancouverhistory.ca. Retrieved 17 February 2014.
  2. "Happy 80th Birthday to the CPR Dunsmuir Tunnel, Vancouver, BC ..." flickr.com. Retrieved 17 February 2014.
  3. Bollwitt, Rebecca. "Tunnels Under Downtown: Vancouver History Readers' Choice". miss604.com. Retrieved 17 February 2014.
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