LRT and Subway Myths
In the debate over rapid transit, there are a number of myths that are repeated over and over again. Some incorrect beliefs about LRT can be explained by the fact that not many people in the Toronto area have experienced true LRT, but there are also a number of incorrect beliefs about subway technology.
Click on the myth to reveal the truth behind it. To comment, make suggestions, or even dispute points, post a comment on this blog page:
To a small degree, this is true. However, tunnel boring machines (TBMs) have to be placed in the ground somewhere and removed somewhere else.
Also, each location for stations and emergency exits requires a major excavation. This upper photo to the left shows how traffic on Keele Street at Finch has been reduced to a single lane for the construction of the Finch West subway station. North of the intersection, there is no northbound traffic and a detour must be taken around the construction.
Compare this to the surface transit construction taking place on Highway 7 between Bayview and Warden. Just like LRT construction, this BRT project involves building a private median for transit. However, unlike the subway construction at Keele and Finch, all through lanes of traffic have remained in full use during most of the construction.
As the lower photo to the left shows, there remains three lanes of through traffic in each direction, exactly the same as there was prior to construction.
This is a recent myth that the anti-LRT crowd has come up with to counter the lower construction costs of LRT.
It stems from the fact that a subway train can carry more people than an LRT train, and therefore be more cost-effective to operate, even when there are two-person crews operating them. This translates into a slightly lower cost per passenger, NOT a lower overall cost to operate a subway line over an LRT line. A subway line has numerous additional maintenance, operating, and security costs that also come into play.
If a subway line is placed in a corridor where the demand can be easily met with LRT, the operating costs of the subway do not decrease, but the per passenger operating cost skyrockets. Even considering that a subway may have the effect in some situations of attracting 10-20% more riders than an LRT would, the per passenger cost of operating that subway line is substantially more than the per passenger cost of operating the LRT.
Whether one mode is first-rate or second rate is based on its appropriateness to the situation.
Both technologies have similar top speeds. How fast a train can get from one end of the line to the other depends on how often it must stop and how long it must stop to load and unload. Stop spacing is significantly affected by the cost of a station, and either mode will have expensive station infrastructure when placed underground. This translates to the need for wider spacing between stations. This means that the train will tend to have an overall higher average speed.
However, longer station spacing can slow down the average trip for a number of reasons. First, there is added travel to get to and from a station either by walking, driving, or taking another transit vehicle, often a bus. Second, vertical travel is often forgotten in considering how long one's trip takes. That is, how long does it take to get from street level down to the platform? And then there is dwell time: the time it takes to unload and load. The further the stations are from each other, the more people have to enter and leave at each station, making the stop time increase for trains.
Whether one mode is first-rate or second rate is based on its appropriateness to the situation.
It is true that LRT carries fewer people - that is where the word "Light" comes from in its name. That does not automatically make it second-rate to a subway. Where the demand for subway capacity for now and the foreseeable future is not there, the added up-front and on-going operational costs of subway make it second-rate for the situtation.
What if we end up needing far more capacity 50 years from now? That is a good question, if we are looking at building a single transit project and then not building anything further. Ever. As future needs change, much of those needs should be met by building other parts of the transit network and not by trying to increase capacity on what we already have. Trying to build one thing that will suit us so far in the future is actually not planning for tomorrow.
Of course, it must be noted that the demand on the Yonge Subway line is now exceeding its capacity, the powers that be have been wasting time on trying to squeeze more capacity out of what is there instead of enhancing the network with the construction of a Downtown Relief Line. Is it any wonder why we are concerned about future capacity? Let's work towards continued network expansion, and stop perpetuating the idea that each project unto itself must carry the load on its own for generations to come.
Both subways and LRTs run on track that must be replaced every 20-25 years, and more often in places of heavy wear. They both use vehicles that must be replaced every 30-35 years.
Underground infrastructure is expected to last longer, and this is where the myth of the "100 year lifespan" comes from. Even this is incorrect as anyone having to travel up Yonge Street late at night are aware. The subway has been closed for overnight work because it was found that the tunnels are being "squashed" after only 40 years. Once circular tunnels have become oval due to this effect and work is being done to prevent what this will eventually lead to. All that "100 year" infrastructure comes with 100 years of operational and maintenance costs!
The Scarborough RT is not Light Rail Transit. It is a "mini-metro" line. A little history of this line is needed for background...
Original plans for a suburban light rail line go back to the mid 60s that had a line connect with the Bloor-Danforth subway line at each of its ends with a northern cross-town connection. In the early 70s, the Ontario government got into the transit vehicle designing business and had plans for a mag-lev train. That development did not get very far, and a linear induction propulsion system survived and became part of an automated Intermediate Capacity Transit System (ICTS).
With extensions on the Bloor-Danforth subway line to Kennedy and Kipling, provisions were built at both stations for the future suburban LRT line, and plans were already underway for the east section to the Scarborough Town Centre. However, the Province wanted a way to showcase its new ICTS product and offered to pay the difference in cost. To minimize these extra costs, as much of the original LRT plan was adapted for the new ICTS plan, which set in motion the replacement issue now facing us.
Just like subways and LRT, the ICTS vehicles have about a 30-year lifespan and that takes us to 2015 when most of the SRT cars will be that old. In the meantime, the Province sold its transit vehicle business to Bombardier Transportation. Bombardier developed a new generation of vehicles that are larger in size. Vancouver's SkyTrain uses both the original (Mark-I) cars and the newer (Mark-II) cars, though not coupled in the same trains. However, Vancouver designed the SkyTrain to be an ICTS system from day one, unlike the SRT which was an adapted plan.
Bombardier no longer makes the Mark-I cars, but they can put them back into production for a price. As there are some tight curves and clearances on the Scarborough RT line (remnants from the original LRT plan where these are feasible), the new Mark-II cars will not fit without some major reconstruction. Thus, the Scarborough RT needs major work to be done.
There is not much difference in cost of the three options: paying the price to have more Mark-I cars made, upgrading the line to permit using Mark-II cars, or converting the line to true LRT. Forget getting more Mark-I cars, since another costly choice will be needed when they need replacing in 30 or so years. Converting the line to Mark-II will seriously limit, or more likely prevent any future extension of the line as the technology has a per-kilometre construction cost approaching a full subway. Both of those options will also require a new maintenance facility. Converting the line to true LRT will leave the cost of extensions more feasible, and will allow the shared use of a maintenance facility needed for another line, such as the Eglinton-Crosstown or Sheppard East line.
Aside from the fact that St. Clair is a legacy streetcar line that runs on a four-lane street with on-street parking, the disaster that occurred on St. Clair was the project itself. The emphasis is on the project, as the problems that plagued St. Clair are not necessarily unique to St. Clair. Any other project, INCLUDING SUBWAY CONSTRUCTION, could possibly be subject to the same disastrous effects if the city fails to learn from its past experience.
Poor management of the St. Clair project resulted in uncoordinated scheduling between the construction of the streetcar line and various utilities such as Toronto Hydro and Consumers Gas. This mismanagement should not have occurred with St. Clair, but to say that LRT construction is doomed to the same occurrence forgets that the same can be said for any subway construction project.
It should also not be forgotten that the St. Clair project was delayed an entire year while an unsuccessful law suit made its way through the courts. That could happen with any project, including subway construction.
Heavy snowfall will have an effect on any mode of transit that is not covered such as being in a tunnel, so this point is only valid when comparing underground versus at-surface construction. That said, a vehicle on rails is less affected by heavy snow than vehicles on roads.
Where this point resonates with transit riders is when fingers are pointed at the Scarborough RT. The trouble is, the SRT is not true LRT, but a mini-metro system with linear induction propulsion. Motors work when electric current generates magnetic fields between a moving part and a stationary part. With conventional rotary motors, the moving part is on the shaft of the motor and the stationary part surrounds it, and the magnetic field causes the shaft to spin. On a Linear Induction Motor (LIM), the moving part is on the bottom of the train and the stationary part is on the ground between the rails, called the "reaction rail".
In both types of motors, the gap between the moving and stationary parts must be small: about a few of millimetres. With a rotary motor, this is completely isolated from any weather, whether or not the train itself is. With a LIM, it is open to the elements and ANY snowfall is problematic, not just heavy snowfall. When a train passes over a section of the reaction rail, electric currents are induced in it in order to create the magnetic fields necessary to move the train. However, electric currents have a slight heating effect on the reaction rail and causes snow to melt. After the train passes, the melted snow freezes. As more snow falls and more trains pass, a thin layer of ice builds up on the reaction rail and when it gets more than a few millimetres thick, trains shut down.
Light Rail Vehicles use rotary motors and are not subject to this problem.