Wednesday, February 9, 2011

Calgary's Downtown Transportation Network


Calgary's Downtown LRT Corridor

Due to a switch in offices I now labour in at location where commuting is possible with Calgary's LRT.  My oh my, there are many issues with Calgary's downtown setup that I have since discovered.  The Calgary LRT system utilizes a combination of older Siemens U2 vehicle and various models of the modern Siemens SD-160 vehicle.  Both models have a maximum capacity of approximately 260 people per vehicle.  Each train in operation can only have three vehicles, since the downtown platforms are only the length of three LRT vehicles.  This means that each train can only hold about 750 people.  However the downtown stations have been undergoing an overhaul, with a new platform length allowing four car trains by 2012.

Each train passing through the downtown during peak hours (7-9am, 4-6pm) are often at maximum capacity, especially the Somerset-Crowfoot line. This means that each train is carrying at least 500 people aboard.  There are two lines that run through the downtown Somerset-Crowfoot, and Downtown-McKnight, and at peak times both lines run at 5 minute frequencies.  This means a train is passing by one way every 2.5 minutes, and 1.25 minutes both ways.  This means that the downtown corridor during any peak period has five trains each way, or 5000 passengers. 

The design of the downtown LRT corridor is efficient in that platforms are minimalistic and allow patrons to get to the train quickly.  The LRT corridor runs along its own right-of-way, which means that automobiles cannot travel along the road.  The right of way also runs at grade, which means that intersections with vehicle traffic are not grade separated, this is good since Calgary was able to build the corridor inexpensively. 

However the problem with the LRT corridor is that the transit vehicle is not given priority at every intersection.  The intersection traffic light sequence runs on a cycle, so a train has to wait for the light if it arrives at the intersection later than it was scheduled to.  I do not know why Calgary does not change this, they are basically saying that it is more important to move 15 cars rather than 500 transit riders.  How does that in any way make sense?   With the current set up it takes 10 minutes to travel 2 km, at an average speed of 12 km/hr. 

What can be done to improve this dilemma?  500 people should not have to wait for 15 people, when a train approaches switches should be triggered to change the light immediately for a seamless commute for the higher volume transportation mode.  This would shave off 3 minutes at least of travel time through the core. 

The fact that the Downtown-McKnight line terminates downtown does not help either, since all of the trains for that line have to stay downtown and there is no immediate exit for them on the west end.  This problem will however be corrected in 2012 when the new West-LRT expansion opens, and continues the McKnight line west past 10th Street SW station out of the core.


Calgary's Downtown LRT Corridor
As the above map indicates with the bubbles, there are 18 total LRT-car crossings.Four of these crossings are for east-west traffic near the outskirts of downtown.  The remaining 14 crossings are the result of north-south vehicle traffic.  The crossings are divided into crossings with no immediate downtown exits (red) and crossings that have direct downtown exits (blue).  This means that the city is causing the LRT system to stop unnecessarily at the 10 red intersections.  The north-south red intersections could be eliminated since they cannot cross the CN rail right-of-way.  The remaining six north-south blue intersections could be halved to 3 intersections by converting the roadways from their existing one-way traffic design to two-way traffic.  Essentially 10 north-south redundant crossings could be eliminated increasing the speed and convenience of a more heavily utilized and sustainable transportation mode.

In the past week there has been three separate occurrences of vehicle collisions which caused 10-15 minute LRT delays, since the collisions happened right on top of LRT tracks cutting off access to the core.  The elimination of 10 intersections would greatly reduce the occurrences of service interrupting accidents.  Every accident that occurs has the potential of affecting thousands of LRT commuters until the way can be cleared, costing tens of thousands of dollars in lost working time and LRT operations.

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