“Private vehicles will continue to increase regardless of whether PAREX is built or not.”
“Private vehicles will continue to increase regardless of whether PAREX is built or not.”
Various environmental, heritage and mobility groups are opposed to the 19.37-kilometer Pasig River Expressway project and want it stopped. They have three main reasons, foremost of which is the induced-demand phenomenon. The other two reasons are environmental and heritage degradation.
Let us look at the first reason because it is technical and seems to be the core of their argument. This induced demand phenomenon stipulates that when new roads are built, which in this case is PAREX, this will induce or attract more traffic which will eventually cause more congestion instead of alleviating it.
Induced demand is not new. It was first noticed by road engineers in 1930. Robert Moses, the famous urban planner who transformed New York City, also noticed it. His solution was to build more roads which just increased traffic congestion. By the 1970s, induced demand was already accepted among urban planners, traffic and road engineers. Consequently, some planned road construction projects in some local government units in the United Kingdom, the United States and a few other countries were discontinued. This is now what these various groups want to do here with the PAREX project — scrap it.
Judging by the reactions of some cause-oriented groups who are now supporting the scrapping of the project, they really believe the reasons given are gospel truth. They however, have to be careful in overemphasizing the importance of induced demand as the only determinant that influences traffic behavior because there are other factors.
The critics may be right that PAREX to a certain extent will affect traffic volume but not to the extent calculated by them. This is because there are other ongoing projects in the metro area in conjunction with PAREX which according to reputable traffic and transport studies will balance out the negative effect of induced demand. These are the MRT7 project, the LRT1 extension project, the on-going subway project, the recently approved MRT4 project, and lastly, the just completed extension of LRT2. When all these projects are completed, this will lessen the need to use private vehicles. Hence, induced demand would also be reduced. If we dig deeper into what this induced demand phenomenon is all about, we will come across many other kinds of demands and therefore a lot more complicated.
From the way they explained induced demand, they are following some researchers who “try to isolate generated demand as the sole effect of induced demand” which is not always the case because there can be other explanations.
There is also such a thing as latent demand, dissuaded demand and a few others like diverted travel. All these must have been factored and studied by the proponent and the Department of Transportation before greenlighting the project. Various studies by universities and experts also suggest that “when data from 1982 to 2011 were analyzed, additional roads actually reduced the rate of congestion increase. When increases in road capacity were matched to the increased demand growth, congestion was found to be lower.”
In the case of the six-to-eight-year study of Professor Robert Cervero of UC at Berkeley about highway expansions, he found that “20 percent of the added capacity is preserved. The other 80 per cent is absorbed or depleted. Half of it was due to external factors like growing population and income. Only half of the 80 per cent is due to induced demand.”
There is therefore an argument to be made that building PAREX may not be so bad after all, at least from a technical point of view. It is not also true that there are no elevated freeways in San Francisco or freeways in Paris. The last time I was in San Francisco, there were still elevated freeways unless the city tore them down. Paris also has freeways. The A1, A2, A3, A4 and A5. If the circumferential freeway is included, that would be the sixth. And yes, a portion of the Paris circumferential freeway is elevated.
In Tokyo, there are roads constructed along rivers. In Boston, the freeway was constructed below the river. Most major metropolitan areas all over the world have urban freeways for easy access and exit of congested metropolitan roads which is something we badly need in the Metro area. We have completed the SKYWAY project which is the North-South corridor.
The PAREX is supposed to be the East-West corridor that will interconnect with the SKYWAY thereby allowing easier access and exit anywhere in the Metro area. If this can be achieved, then people will be encouraged to move to the outskirts thereby expanding Metro Manila’s urban sprawl.
Lastly, we must remember that the current road network of Metro Manila is totally inadequate and that private vehicles will continue to increase regardless of whether PAREX is built or not.
