The loading standard, by definition, accommodates the pent-up demand by always ensuring there is spare capacity along the line. As more people ride the line, the number of people per vehicle increases, which in turn triggers more vehicles to be added to the line.
The peak-period
TTC crowding standards are:
CLRV: 74 people
Flexity: 130 people
But the manufacturer's vehicle capacities are:
CLRV:
133 people
Flexity:
251 people
The problem on King is that the TTC is physically unable to add enough streetcars to keep the line within the crowding standards. This is for a couple reasons:
1. There aren't enough streetcars in the fleet to run the service which should be run.
2. Even they did remove streetcars from other routes to put on King, the increased frequency could exceed the practical capacity of the street itself, causing the line to grind to a halt as every vehicle gets stuck behind every other vehicle (think Line 1 when there's any kind of delay during rush hour).
The practical capacity of the street is based on the signal cycle, which can be as long as 120 seconds. It's not consistently possible to get more than one streetcar through per green, because it then sits on the far side serving the stop, preventing any subsequent vehicles from proceeding for about 30 seconds. If a streetcar enters the intersection at the start of the green (i.e. was waiting at a red light) it might leave the stop just in time for a following streetcar to enter the intersection just before the end of the green, but we can't really count on that.
Currently the scheduled service frequency and loading-standard capacities on King are:
15 CLRVs/hour on the 504
7 Flexities/hour on the 514
5 buses/hour on the 503
and some extra CLRVs, but we don't really know how much that increases the frequency. Let's say 2 extras per hour.
The combined frequency is about 29 vehicles per hour, which is an average headway of 124 seconds. That's roughly equal to the practical capacity of the street, so adding more vehicles to the line may make things worse rather than better by increasing streetcar-to-streetcar queuing at signals, which increases travel times, which in turn reduces frequency. So the speed would go down and the capacity would stay the same.
The most practical way to increase the physical capacity of the line is to use bigger vehicles. Multiplying the vehicles in the current schedule by their loading standard provides a total capacity of
2423 people per hour. In comparison if all 29 vehicles per hour were Flexities, the capacity would be 3770 people per hour (a 64% increase).
Also in comparison, a 4-lane urban road can carry about 900 automobiles per hour per direction in ideal conditions (no parking, no loading, no bicycles, no transit, no left turns, no right turns etc), which is about 1000 people per hour at the average 1.1-1.2 vehicle occupancy.
In a more short-term basis, I see a couple ways of increasing the line capacity:
- convert the 504 from CLRVs to Flexities on a 1:1 basis as quickly as possible, which is
exactly what the TTC is doing. But that's subject to deliveries from Bombardier given that it's not politically viable to take them from routes that have already been designated fully wheelchair-accessible.
- convert the 503 from buses back to CLRVs, and extend it as far west as practical (Charlotte loop?)
