There is something common in New York, Portland, London, Hong Kong, Singapore, New Delhi, Mumbai and Sao Paulo. These metropolitan cities are examples of Transit Oriented Development (TOD) around the World.
New York City Subway caters to an area of 1,213 sq. km with a total population at about 20 million while Portland Streetcar caters to a smaller area of 375 sq. km with population served at 0.6 million. Delhi Metro serves an area of 1,590 sq. km and a total population of about 22 million.
TOD in these cities provides an option for mobility for all residents and encourages the shift to public transport. It promotes better management technique and makes traffic management more feasible. By incorporating this concept mixed-use housing development is promoted which eventually enhances the quality of life. The concept is less expensive than construction of a long network of roads and highways. The solution helps to reduce expenditure on transportation and provide economic stimulus.
The principles guiding TOD are promotion of non-motorized transport and also pedestrian-friendly environment to prompt environment friendly cities, creation and maintenance of densities between network, connectivity with the community, ensuring safe use and citizen-friendly public transport facility, allocating a certain radius around the transit station as mixed-use along with high density and walkable development and encouraging the development of multi-modal interchange.
The need for such development arises to make public transport more convenient for public use. Every citizen should have a safer, faster and easier access and should be able to leave private vehicles and shift towards other modes of transport. TOD promote climate resilient cities by reducing the volume of vehicles on roads through the promotion of public transport. As this development contributes to reducing environmental degradation and minimizes urban sprawl, TOD act as a major contributor to solving the growing climatic issues by creating dense, mixed-use and walkable communities.
However, all positive said about TOD, there are concerns related to TOD increasing the property values and attracting wealthy people, thus, leading to gentrification process pushing low-income families away from transit.
A study on neighborhood change surrounding transit-oriented development by Randal O'Toole published by the Dukakis Center for Urban Policy at Northeastern University claims that one of the disadvantages of gentrification around transit stations is wealthier households tending to own more cars and use transit less than poor households. The research found transit investment frequently changing the surrounding neighborhood. While patterns of neighborhood change vary, the most predominant pattern is one in which housing becomes more expensive, neighborhood residents become wealthier and vehicle ownership becomes more common. And in some of the newly transit-rich neighborhoods, the research reveals how a new transit station can set in motion a cycle of unintended consequences in which core transit users - such as renters and low-income households - are priced out in favour of higher-income, car-owning residents who are less likely to use public transit for commuting.
The challenge is doing the cost-benefit analysis around the cited numerous and diverse benefits of TOD which considered individually do not necessarily justify major transit investments but a sum of all benefits may justify the high-quality public transit and transit-oriented development.
Arefeh Nasri and Lei Zhang produced an interesting study on TOD in Transport Policy published by Elsevier in 2014. They say that there has not been enough research done on how successful TODs are in providing sustainable transportation modes, which will eventually result in less energy consumption, environmental pollution, and trafﬁc congestion in urban areas. Their study tries to understand how travel behavior is different for TOD residents in the two metropolitan areas of Washington, D.C., and Baltimore by examining the changes in vehicle miles traveled in order to analyze the effectiveness of TODs on encouraging driving less and switching to transit, walking, biking, and other sustainable modes of transportation. The results of study indicate that people living in TOD areas tend to drive less, reducing their vehicle miles traveled by around 38% in Washington, D.C. and 21% in Baltimore, compared to the residents of the non-TOD areas even with similar land use patterns.
In India, of course, the spread of Delhi Metro is frequently cited as a reason for soaring real estate prices in areas having easy access to Metro network, the ease of commuting has greatly enhanced leading to the lesser use of private transport and thus reduction in vehicles on Delhi roads.