Congestion in the Metropolis

We call it a traffic jam.  That’s when the number of vehicles that want to use a road space exceeds its capacity.  And since capacity is measured in number of vehicles per unit measure of time, both the number, and speed, affects traffic congestion.  The worse thing is, since congestion slows down traffic, the capacity of a road actually decreases as the level of congestion increases, further multiplying the incapacitating effect.

The number of complaints over the deteriorating traffic situation in the metropolis is likewise increasing in a geometric manner, meaning it is increasing and the rate of increase is also increasing.  Sooner than we think, it will reach such a situation same as that as inflation, which are often described as “spiralling” or skyrocketing,” which means getting faster that we could respond and cope with the gridlock, not to mention unravel it.  As we have mentioned in the past, mass transportation is the only plausible solution, but it takes 5 to10 years to gestate.

Traffic congestion in a large city has two characteristics – the “when” and the “where.”  It does not happen at once, nor does it happen all over – it starts somewhere and on specific times of the day, then creeps slowly, getting larger in timespan and affected area, until you have a metrowide congestion phenomenon.  This is reminiscent of Bangkok’s gridlock in the early 1990s, when buses have toilets at the back and the portable urine bottles went on sale.

First the place.  We may need to reiterate a few times over that congestion almost always starts at intersections.  And for perfectly good reasons – no two things can occupy the same space at the same time – a rule that we learn as far back as high school.  Road network systems are composed of road links crossing each other at intersections, which, more often than not, have the same number of lanes in both/all directions as the corridors themselves.  Thus, traffic has to stop and go, stop and go, decreasing overall traffic speed by half.

When an intersection becomes congested, it cannot adjust by itself.  Thus queues form, the length of which, depend on the excess number of vehicles trying to use the intersection.  These lines extend outwards from the intersection, depending on where the most traffic is coming from.  In the early mornings when people go to work or return home at dusk, pockets of these lines start to appear in certain intersections of the city.  This is because the number of vehicles constantly increases every year while road space is not expanded at the same rate.  Then the lines meet between two congested merging them together.  Eventually, you have one gigantic traffic jam!

Similarly, timewise, congestion starts to happen at peak hours, say 6 am to 8 am, and 4 pm and 6 pm.  People get angry because the time to travel to work gets longer but we have no choice but to adjust – we leave earlier, and in the evening, we dilly-dally by passing through the mall; some opt to dine out, while others make the excuse to drink and entertain themselves while waiting for less traffic on the road home.  This is why in cities where traffic is a daily problem, more and more people don’t go home at 5 o’clock.  Manila is a good example.

As traffic congestion become worse over the years, the peak hours are stretched, too, from 6 am - 9 am and 4 pm – 7 pm.  There’s a small peak at lunchbreak, too but it ain’t much.  However, congestion creeps in as the road infrastructure can’t contain the sheer increase in traffic volume.  Eventually, the morning peak merges with the noon peak, which in turn merges with the afternoon peak, such that you will one find yourself in a city where it’s always a traffic jam at any time of the day, except like in Manila where you have a freeway between late night to early morning, or during a Pacquiao fight.  But even those two may not last.

I hate to say this, but the way the pockets of traffic congestion in the metropolis are creeping slowly all over the city, we may see a few gridlocks in 2013.  Let this be my way of saying Happy New Year to everyone.  Enjoy the year-end traffic jams while they last.  They’ll only become worse in the New Year.  But as they say, smile and enjoy the day and the rest of the year!