Though construction on Phase-I of the Metro commenced just some months ago, the rapid expansion of its network will determine what the city's transportation will be like in the future.

As ideas for future Metro Rail corridors gather ground, with the Governor's address to the Assembly on Friday announcing that three new links are being considered, the place that the Metro project occupies in the city's transportation grid has come into focus.

A detailed project report will soon be undertaken by the consultant, Delhi Metro Rail Corporation, to determine the feasibility of corridors between Moolakkadai-Thirumangalam, Moolakkadai-Thiruvanmiyur and Luz-Poonamallee through Iyyappanthangal.

Populated areas

K. Rajaraman, Managing Director of Chennai Metro Rail Limited, said that the routes were chosen by identifying thickly populated areas in the city that currently do not have access to an effective mass transit option. When the population coverage was mapped on to the city's transit network, there were quite a few large gaps.

Though construction on Phase-I of the Metro commenced just some months ago, the rapid expansion of its network will determine what the city's transportation will be like in the future.

H.M. Shivanand Swamy, executive director of the Centre for Excellence in Urban Planning at CEPT University, Ahmedabad, says “People would always choose to live in a locality which is accessible. Mass transit networks play a key role in determining how any city expands.”

Pointing to London, which is about the same size as Chennai, having a 500-km mass transit network, he says that based on current demographics, most Indian cities would double in size within the next 30 years before population growth stabilises. “Metro systems must rapidly branch out towards suburban areas. Those localities are going to become the centres of activity tomorrow. We must start building up capacity to prepare for the poly-centric cities of the future, which will have more than one city centre,” he adds.

The Shanghai Metro, for example, which commenced operation in 1995, has already expanded to a 420-km network. It surpassed the London Underground as the longest urban rail network in the world in early 2010.

Massive transit problem

Acknowledging the importance of branching out into suburban areas, Mr.Rajaraman, however, said it is not possible at the moment as there is a massive transit problem within the city itself. “Nearly 30 to 40 per cent of the city's residents do not have access to any mass transit system,” he says.

He added that CMRL's current model of financing cannot sustain expansion along routes that do not show a high degree of travel density.

On the issue of financial viability, M.N. Murthy, researcher at the New Delhi-based Institute of Economic Growth says since new Metro corridors take time to build up ridership, “a network instead of a line approach should be adopted in evaluating new lines”.

This approach would potentially enable future new lines to be implemented a few years earlier, so long as the entire rail network remains viable.

According to his case study of the Delhi Metro, the social return from greater mobility, in the form of more economic activity and lesser pollution, is much higher than financial rate of return. He estimates the rate of return to be 22 per cent, which means for every rupee of investment, 22 paise is earned.

One more important facet that any expansion plan would have to factor in is greater integration. For example, in Singapore, 25 per cent of the commuters use the Metro systems, but 60 per cent of them combine it with a bus trip.

Metro systems such as the one in Los Angeles finance, build, and operate their own feeder bus systems and bicycle tracks.

(This story was amended on January 11, 2011)

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