Environmental concerns are often cited as one of the main reasons to support the new rapid transit project. And certainly any project that reduces low occupancy vehicular traffic does have some environmental benefits.
But if one is to judge the true environmental impacts of a mega-project we must look at more than just the changes people will make in their transportation choices. What about the recourses that will be consumed constructing the tunnels and the elevated track?
This type of narrow thinking sometimes occurs when we look at solutions to environmental problems. Often technological options are seen as the best or only solution. We often neglect choices which would mean reducing consumption. Usually it seems that the best solution is combination of technology and reduced consumption.
For example, hydrogen is often toted as the solution to pollution and our petroleum dependency. Yet, the current methods used for the production of hydrogen can create just as much pollution. Hydrogen could be part of the solution but it must be combined with an overall reduction in energy consumption.
When it comes to making choices about protecting the environment we need to take a more holistic approach.