No, it cannot.

The Light in LRT refers to its capacity, not to the weight of vehicles or size of rail that it runs on. Naturally, this means that it carries fewer people by definition. But if it costs only a fifth to a quarter the price to build, can we attain the same or greater capacity spread over a wider area with two or three parallel lines?

This would not only save money, but allow for a less costly expansion at a later date when added capacity becomes necessary. At the same time, being ablet to build parallel routes or an actual network of routes leaves us with functional service when a disruption occurs.

This value is a product of two other values:

• How many passengers fit comfortably on a vehicle?
• How many vehicles can pass a given point in an hour?

Number of vehicles per hour is a product of two values:

• How many vehciles can be coupled into a train?
• What is the minimum time between trains?

Are we going for a world record here? Images of clowns spilling out of a car notwithstanding, there is a figure called crush load that is sometimes used. This is the absolute maximum number of passengers that may fit on the vehicle - the worst case scenario. We are not talking about that figure.

Specifications for various vehicles will quote a value that represents a comfortable maximum. The number of seated passengers is simply the seat count on the vehicle, and the number of standees represents a comfortable maximum number of people standing. The standee value is based on a maximum density, often in the range of three people per square metre.

The total capacity of the HRV is 250, while the LRV is 184. To make comparisons simpler, the rest of this page will use 250 for HRVs and will round down to 175 for LRVs.

Subway: 1500

For Subway, train length is primarily a function of station length. For the TTC's Subway system, this is six cars on the YUS and BD lines, but only four cars for the Sheppard line (provision exists to finish Sheppard stations to a full six car length). For the compaison, six car trains will be used for Subway.

LRT: 350-525

The flexibility of LRT allows it to operate in tunnels, on an elevated structure, on a ground level non-fenced right of way, in the median of a road, or even in mixed traffic. To take advantage of this full flexibility, station lengths can become an issue when spacing between cross streets become an issue. Newer generation LRVs can have lengths in the 24 to 30 metre range. For the most part, full flexibility can be achieved by limiting train lengths to three cars (525 passengers). Transit City lines will likely only use two car trains, for a capacity of 350.

Underground/isolated LRT: up to 875

There has been talk about revisiting a Downtown Relief Line (DRL) in Toronto. Some of this talk has suggested a southward extension of the Transit City Don Mills LRT line. Given that this like will arrive at Pape station on the BD Subway line underground, such an extension is likely to also be underground. In such an arrangement, station size is not limited by city blocks or other surface constraints. For the purpose of comparison, the example of Edmonton will be used, where underground LRT stations were built for a maximum train length of five cars.

Subway: 24 (up to 32 in the future)

Currently, the TTC runs trains on a headway of about 150 seconds. That translates to 24 trains per hour. Over the next decade, an upgrade to the signalling system that includes Automatic Train Control (ATC) will improve this. Some have suggested 90 second headway possibilities, but it is doubtful that this will be achieved. With all trains turning back at the same terminals on a line, the minimum practical headway is 140 seconds. With some trains short-turning, this headway will be improved. This will occur when/if the Spadina line is extended north of Steeles - look at this document in the paragraph titled Steeles West Station if you don't believe what is written here.

Despite these improvements, it is not likely that the headways can be reduced below 110 seconds, or about 32 trains per hour.

LRT: 15

It has been suggested (see this article by Steve Munro in the fourth paragraph under the title What Can LRT Reasonably Carry?) that the minimum spacing for on-street operation (still in a median ROW) is four minutes. This translates to 15 trains per hour. Anything below two minutes is not practical due to traffic light timing, even with transit priority.

Planning for the Sheppard LRT line is looking at a minimum headway of 5 minutes, which is 12 trains per hour.

Underground/isolated LRT: 30

Closer spacing can be easily obtained when not dealing with surface traffic lights along the route. It can easily be argued that 90 second headway is possible in this situation, especially when we are looking at some trains continuing on a line at surface while some other trains turn back and remain underground. For the purpose of this analysis, a 2 minute headway will be used.

Subway: 36,000

24 trains per hour with 1500 passengers per train is 36,000 passengers per hour. If headways can be brought down to 110 seconds, the figure increases to 48,000. To compare with today's reality, the Yonge Subway line currently carries about 40,000 passengers per hour during rush hour. These passengers are packed in a little tighter than the rating for comfortable standees, but you probably already knew that!

LRT: 5,250 to 7,875

15 trains per hour with 525 passengers per train is 7,875 passengers per hour. Even with 2-car trains on this headway, the capacity is 5,250.

Underground/isolated LRT: up to 26,250

30 trains per hour with 875 passengers per train is 26,250 passengers per hour. This figure is assuming 5-car trains with 2-minute headways. Even with 4-car trains on a 3-minute headway, the capacity is 14,000.

Note that the Spadina extension north of Steeles will only carry every second train (and perhaps only every third). For confirmation of this, look at this document in the paragraph titled Steeles West Station. The same will have to occur on a Yonge extension in order to increase capacity for the rest of the line. This means that the capacity of these extensions will be, at best, half of the normal capacity: 18,000 to 24,000 passengers per hour.

This is not a capacity issue, as there will not be anywhere near this demand on either extension.

What is does mean is that the frequency of service will be half of what we are used to for the rest of the line. For commuters, that means:

• waiting longer for a train to depart during southbound commutes

• having a 50% chance of boarding a train terminating at Steeles for northbound commutes

LRT from Steeles can provide the needed capacity, and do so with shorter headways.

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This page last updated May 17, 2008