©2001 Get On Board!PRT
By D.S. Gow

After slogging through "This Is Not What I Ordered", the casual reader might be mystified at the characterization of transportation as a consumer product, alongside coffee, tea, or toothpaste. This is understandable. We are not used to thinking of transportation in those terms. When it comes to our private automobiles we see them as extensions of our homes, or even our personal space. The cliche "excuse the mess, I kind of live out of my car" is often too true. Likewise, rapid transit is just this Thing that simply exists, like the municipal water supply or telephone poles. If the train or the express bus stops at a convenient distance from your home then rapid transit is part of your world. Otherwise it's irrelevant.

This irrelevance is important when considering transit policy: if a type of transportation is irrelevant, is it really a choice? Public policymakers and transit planners can call a light rail or monorail system an "alternative", but I maintain that if lack of access and overall low speed (when compared with the OTHER choice, the private car) render it irrelevant to most people, then it's not really a choice. So let's take a look at conventional rapid transit's service characteristics in order to identify the source of this irrelevancy.

In Part I we found that conventional transit doesn't go where you want, when you want, as fast as you want. The root reason is that conventional transit only goes back and forth along a corridor, and it only stops at stations that have a fair amount of distance between them. And it can't really be any different: today it is too expensive to have very many train corridors within a metropolitan area, the construction cost is too high, the right of ways and stations claim too much land. And then comes the clincher: The people who are supposed to use the system do not all live in those corridors, and nor are all the destinations to which they wish to travel. Dr. Martin Lowson, designer of the British ULTra personal rapid transit system, characterizes modern urban transportation patterns this way:

"...demand in a modern city is anywhere to anywhere. It would be almost impossible to devise a conventional collective transport system to meet these very diverse needs." Source

From anywhere, to anywhere. No wonder transit restricted to corridors lacks appeal, and no wonder they make little or no impact on traffic congestion. A corridor simply cannot serve a city that spreads out north, south, east and west. This is especially true in the low density, spread-out cities of the western United States.

When you hear predictions about light rail or monorail ridership, they sound pretty good. They propose trains with x-person capacities, running y-minutes apart, and a few simple calculations later ridership levels of z-thousands of passengers per hour in each direction are being projected. The truth is that their estimates rely on forcing as many trips, which originate 'anywhere' and terminate 'anywhere', into a narrow corridor in which a line-haul train system runs back and forth. But access to the system is convenient only for people who happen to live near a station. Achieving anything approaching the projected ridership goal relies on getting riders from their starting point to the corridor, and then from the corridor to their ultimate destination. This collection-distribution system is called "feeder transit".

But feeder transit adds another layer of inconvenience on top of the corridor's limited access. The feeder system, probably a bus, may make getting to the train station possible, but to do so you have to wait for the bus, ride it in congested traffic, maybe transfer to another bus, and then when you get to the station you have to wait for the train. And the train only takes you to another station, you may have to do the bus ride all over again to get to where you want to go. And then if you're on a round-trip...

Is it any wonder most people would rather drive their car? Access is easily at hand; you get to set the schedule; even though you're sitting in traffic, it's just one ride that goes all the way to your destination.

In contrast, Personal Rapid Transit eliminates the transfers. PRT collects riders and distributes them to any station in the guideway grid, instead of forcing all of them into the same corridor. PRT's degree of access cannot be matched by trains, and approaches-- though not equaling-- the door to door service of the automobile:

The chasm between what people want and what transit planners are offering is key to any public debate on selecting a rapid transit technology. A system may be capable of carrying enough people to relieve traffic congestion, but actually getting them to use it is an entirely different matter. Given the expense of conventional rail and monorail, and the poor performance of recent light rail systems, is any kind of train system a fiscally responsible choice? Now are you ready to...

The author has a degree in Policy Analysis from the University of Washington Graduate School of Public Affairs (now known as The Evans School).