The peculiarities of transport demand

Published in The Freeman (Philippine Star), Mar. 22, 2012

Enrique Peñalosa, former mayor of Bogota, Columbia, and the brains behind its famous Transmilenio BRT, often says in his talks that transport is the one peculiar issue that most developing cities face – “When a city develops, all other sectors grows with it – its commerce will become better, education and health will improve, all except transport, which will become worse. And the reason for this observation is due to the peculiarities of transport demand.

The first thing to understand first is that transport, like many other demands, is never constant during the day. Just like power or electricity. During the day, power demand fluctuates. Manufacturing plants, operating 24 hours may have a fairly level demand, a little more at night due to lighting needs, but residential houses are very irregular, low at the early part of the day when people are at work and peaks up at night when people return home, before declining again when people turn off their lights to sleep. It spikes up again the next morning before people go to work. This is why most brown outs are in the evening, when the whole demand is highest.

Traffic congestion is the same, and can be fairly predictable. It’s not flat the entire day, as everyone knows – it’s worst in the morning when people go to work, eases up after 9 a.m., and peaks up again late afternoon when people return home. There might be a slight peak at noon but not as high as the morning and afternoon peaks. If you look around, you can actually see some jeepneys parking around with their drivers sleeping on off-peak hours like 9 – 11 a.m. Or 2 – 4 p.m. Only when a city becomes so congested that you see continuous traffic jams the whole day, easing up only late at night until dawn. When people sleep, both traffic and power demand decreases.

Going back to transport demand and the accompanying modal disaggregation, we said that person-trips maybe categorized by the purpose of each trip, broadly: home-to-work, school or church, personal/family matters, or social/recreational. It may be further segregated into sub-classifications if we want to do such exercise, but one thing for sure, if you look at these closely, we can easily conclude that home-to-work trips comprise easily two-thirds of the daily trips or even more. Try to look at the entire population and see how they travel and for what purposes. The wealthy and upper middle class may move a lot, and have plenty of trips to make, but for the working class, the poor, the lower- and middle-income groups, home-to-work dominates their daily travel habits and takes the bulk of their monthly transportation expenses. And usually, the other trip categories are included in their daily home-to-work routines, like passing by the mall to shop on their way back home from the office, or enjoying a night out with friends, or even passing by the church. Clearly, in planning for transport, the home-to-work trips is a major, if not the prime, consideration. And this succinctly explains why we have a morning peak and an afternoon peak, with a small lunchtime peak, not only in Cebu, but anywhere around the world, especially in rapidly growing and urbanizing centers and megacities.

Transport woes plague growing cities simply because we can’t keep up with the demand – population grows and people travel more as society progresses. Changes in land uses invariably results to more trips at longer distances. The only way to address the urban transformation is either to manage the trips or make transport systems more efficient. As we have stated early on, building more roads will never solve the problem … it never has, in any city in the world. And surprisingly, it will even make it worse! (to be continued)

Leave a Reply

Your email address will not be published. Required fields are marked *