The jam in Delhi’s traffic experiment

A key to understanding the effect of driving restrictions on emission levels would be to analyse what substitutions citizens will make for private vehicle trips during restriction hours

Updated - September 22, 2016 09:22 pm IST

Published - December 28, 2015 02:20 am IST

It will be an unusual start to the New Year for Delhi. The city will be subject to the much-discussed > driving restrictions , according to which between 8 a.m. and 8 p.m. most private vehicle operators will only be able to take their vehicles out on alternate days, from Monday through Saturday, depending on whether their license plate numbers are odd or even.

The restrictions were devised after the Delhi High Court > likened the city to a “gas chamber” and ordered the Delhi government and the Central government as well as the Delhi Pollution Control Committee to produce an action plan to tackle the city’s alarming levels of air pollution. In early December, the city, which had already been declared the world’s most polluted city by the World Health Organisation, > recorded a level of atmospheric particulate matter that was 10-16 times higher than what is considered safe.

Other models Delhi now joins a list of cities including Sao Paulo, Bogota, Beijing, Mexico City and Santiago that have driving restrictions to bring down air pollution. Unfortunately, there is enough evidence to suggest that these programmes do not necessarily achieve their goal of pollution reduction but can, in fact, be detrimental to air quality over the long run.

Consider for instance, Mexico City’s Hoy No Circula (‘“Your car does not circulate today”) programme instituted in 1989 to bring down record levels of ozone. The restrictions, which have evolved over the years and continue today, mean that almost all private vehicles are banned for one day per week. There is sufficient evidence from published scientific studies, discussion papers and direct experiences that suggests the programme did not achieve its pollution lowering objective. Published in the Journal of Political Economy , Lucas W. Davis’s study, “The Effect of Driving Restrictions on Air Quality in Mexico City”, demonstrates that there was no evidence that the concentration of pollutants declined. Citizens did not sufficiently substitute their private car trips for subway, bus or taxi rides. Instead, the number of vehicles in circulation increased, and with a greater proportion of second-hand high-emitting cars.

Other cities have similar stories to tell. In Bogotá, Colombia, traffic restrictions have been in place since 1989, under the Pico y Placa (‘Peak and Plate’) regulations, whose current form includes driving restrictions based on license plates from 6 a.m. to 8.30 a.m. and from 3 p.m. to 7.30 p.m. on all weekdays, and from 6 a.m. to 7.30 p.m. in the city centre. Unsurprisingly, this has not solved the pollution problem; it has exacerbated it. In the absence of an adequate public transport solution, car-owning residents of Bogotá started getting to work progressively earlier, to beat tightening restrictions, says Federico Torres, a transport and infrastructure expert and resident of Bogota. The restrictions simply spread the peak travel hours out, Mr. Torres told The Hindu .

In a recent study on the effectiveness of Pico y Placa, Cynthia Lin Lawell, an associate professor at the University of California at Davis, and her co-authors provide empirical evidence to suggest that across the different versions of driving restrictions, not only was there no significant improvement in air quality, there was actually a significant increase in the atmospheric concentration of nitrogen dioxide, nitrogen oxide, and ozone. The concentration of nitric oxide alone decreased in one version of the restriction. City residents buying second-hand vehicles or making more than one trip during unrestricted hours to compensate for each trip forgone during restriction hours were among the reasons for the policy’s ineffectiveness, Ms. Lawell told The Hindu .

Closer to home, China too introduced driving restrictions in Beijing for a limited period during the 2008 Olympics before making them more permanent. When compared to research on other cities, there is less agreement on whether driving restrictions were effective in Beijing. One cited reason for the more favourable impact on pollution levels, from researchers who reach this conclusion, is that the automobile stock (from which a second car is bought for instance), is newer and more fuel efficient than the Mexican auto stock. Some research findings also say air quality was not impacted, or impacted slightly negatively, while traffic congestion eased up.

Instead of reinventing the wheel, Delhi can build on the experience and learning of its global counterparts. Specifically, those designing and implementing the policy will need to analyse what substitutions citizens will make for private vehicle trips during restriction hours. This is a key to understanding the effect of driving restrictions on emission levels.

According to the Economic Survey of Delhi 2014-15, 31 per cent of Delhi’s households were using bicycles, 39 per cent were using scooters and motor cycles, and just 21 per cent cars.

Change in aspirations In India, car ownership is an aspiration as individuals get wealthier. There are different attitudes to public transport across generations and geographies. In the United States, for example, there is a greater reluctance to use public transport except in large cities serviced by mature metro and bus systems and across Generation Y. On the other hand, most of Europe and parts of East and Southeast Asia (Singapore and Japan, for instance) are more public transport-friendly. At the heart of the longer term solution to Delhi’s current transport pollution problem is a shift in attitudes and aspirations. This is going require a comprehensive strategy from the government targeting all populations from the child in the classroom to the retiree, to create a stronger culture of public transport across the board. Mark Carney, the Bank of England governor, was famously spotted taking the London Underground (subway system) on his first day to work and London Mayor Boris Johnson championed the cause of bicycles around London, so much so that the bikes were known as ‘Boris Bikes’. To think of politicians and high-ranking government officials taking a metro ride to work (except perhaps on its inaugural day) requires more than a little stretch of the imagination.

When underlying values change, behavioural changes are often not far behind. However, shifting values can take time, and transport mode-choice can be influenced concomitantly at the behavioural level. Behavioural economics offers many transport-related experiments conducted in other cities. Behavioural incentives, some of which are already in place in most cities and systems, range from the simple and obvious, such as congestion charging or building speed breakers, to the more complex and subtle, such as providing incentives to companies that allow their employees to telecommute. A careful application of these strategies can help transition larger numbers of people to more frequent public transport use.

If a city were to encourage people through behavioural incentives to use public transport, that posits the existence of a reliable public transport system with sufficient capacity to meet the additional demand. This is certainly not the case in Delhi or most large cities in India. Delhi’s metro transports approximately 2.4 million people per day, according to government data. At the end of Phase I and II of its construction, the system covered 190 km and has a planned expansion to 405 km by 2021. However, according to a 2014 study by the Transport Research and Injury Prevention Programme at the Indian Institute of Technology, Delhi, over 80 per cent of metro riders take long trips of more than 10 km, while only 17 per cent of trips in Delhi are 10 km or more. The research suggests that transport policies need to focus on modes that cater to short trips, including non-motorised transport. Another finding is that the metro overestimated its ridership by at least 75 per cent; planning and forecasting carefully for the remaining phases is crucial. As far as buses are concerned, this newspaper recently reported that despite Delhi’s 4,700 DTC and 1,500 cluster buses, the city has a shortfall of at least 10,000 buses. These are severe bottlenecks to a medium- to long-term solution to the automobile pollution problem.

An opportunity to collect data Is the fortnight of restriction then without value? Far from it. Apart from a reduction in emissions for the period itself, it offers an opportunity to collect limited data; ‘limited’ partly because behavioural changes over a fortnight are not going to be reflective of longer-term behavioural changes if the restrictions were to become permanent. For instance, if the experience of other cities is anything to go by, individuals who can afford to buy one or more additional cars are unlikely to do so just to tide them over a fortnight. Policymakers therefore need to interpret the January data with caution.

This is a wake-up call to other cities to do whatever is necessary to prevent the entirely avoidable position Delhi finds itself in.

Perhaps the most valuable insights from next month’s traffic experiment will not be collected by the government and transport specialists but by ordinary citizens. The January restrictions have already fuelled intense debate in Delhi. Some car owners will have to take buses, carpool, use the metro and learn first-hand what the bottlenecks and frustrations of public transport are — end point connectivity (or lack thereof), capacity, peak hours, ease of interchange from one mode of transport to another, and so on. They will thus become stakeholders in the city’s public transport in a direct way. Companies will think about setting up and reorganising systems and staff to make telecommuting easier. They too will be compelled to become larger stakeholders in the development of public transport.

When the relatively wealthy minority that uses cars has no other choice but to become direct stakeholders in the city’s public transport in a conscious way, and face, albeit for a short while, the difficulties the city’s many but less fortunate citizens face, then there will perhaps be sufficient pressure to give the city’s public transport planning and building the thought and capacity it very urgently needs. This is also a wake-up call to other cities to finish their unfinished metros, procure their electric buses, roll out their intelligent transport systems and do whatever is necessary to prevent themselves from landing in the polluted, congested, cornered and struggling but entirely avoidable position Delhi finds itself in.

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