Post by Steven Dale
How does cable deal with high-capacity rushes? Say, after concerts and at sporting events? Or in the peak of rush hour traffic? Well that depends on a few things:
- What is the capacity of the system in question? If the system in question needs 4,500 pphpd at peak and you’ve built a 3,000 pphpd then lineups will be long. That applies to any and all transit. If your current needs go over 6,000 pphpd, it’s probably best to consider a different technology. Alternatively, you can build multiple lines (see point 4).
- In the case of concerts and sporting events; how close to the stadium/arena is the transit stop? Cities tend not to completely integrate transit stations into arenas and stadiums because no transit system in existence can handle the crush of 60,000 people filing out of a football game and descending on a subway platform. The same is true for restaurants. No 100 seat restaurant can handle 100 people walking in the door at the same time. Instead, the host waits five minutes before seating you so as to allow service to be spread throughout the evening. It’s also the reason you often can’t get a table for 7:00 pm on a Saturday, but can at 7:15. Good transit, like good restaurants, is good at managing the expectations of its riders.
- Where is your cable station in relation to your riders’ point of origin? Ridership on all transit technologies needs to be spread out somewhat and this is often done by locating the transit station 5-15 minutes walking distance from stadium itself. This prevents a system from getting dangerously overwhelmed. LT1M wait times offered by cable, will however, help alleviate some platform overcrowding that naturally occurs with standard transit technologies.
- Are you relying upon one transit station or many? Most people arrive at an event from many different directions and depart an event in many different directions. If the location of your event is such that only one station, heading in one direction is possible, you probably need a high-capacity technology like Metros or subways. If, however, the potential exists to have many people moving in many different directions, then the needed capacity can be spread over the network, preventing choke points. Cable’s low cost makes this possible.
The last point is probably the most important, because a real world example exists to demonstrate:
Upon opening the Santo Domingo Metrocable line, Metro Medellin experienced ridership double what was anticipated. I’ve spoken with Metro Medellin and they themselves have said the 3,000 pphpd system they built was not enough and they required a 6,000 pphpd system. Rush hour line-ups to use the system are a daily occurrence.
The problem stems from the fact that the existence of the Santo Domingo line has drawn riders from other nearby parts of the network who used to use the private buses that service nearby barrios. Because the wait time to use the Metrocable plus walking from Santo Domingo is still less than the time it would take to use the privately-run bus systems, the single Metrocable line has become somewhat overwhelmed. This probably should’ve been anticipated originally, but is forgivable given the unique nature of what they were accomplishing.
Had they to do it over again, one of two solutions could’ve been implemented:
Firstly, just use a 6,000 pphpd system – which wasn’t available when the Metrocable was originally designed.
Secondly, install a second, parrallel Metrocable line with a connection 1 station over from the Santo Domingo connection. This will spread ridership over a wider area and increase total system coverage.
Metro Medellin already has plans to implement the second option. Given that the Medellin Metrocables have been installed for a price of USD$12 – 18 per kilometer (all in, including stations), the option is certainly doable. It will be interesting to see how this pans out.
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Want more? Purchase Cable Car Confidential: The Essential Guide to Cable Cars, Urban Gondolas & Cable Propelled Transit and start learning about the world's fastest growing transportation technologies.
