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International experiences shed light on best practices for congestion pricing in Delhi

This piece was originally published in the Hindustan Times.

Road traffic congestion is a pressing issue in many of India’s metropolitan centres. Gridlock brings prolonged commute times, excessive fuel consumption, air and noise pollution, and elevated greenhouse gas emissions. The National Capital Region has been in the spotlight as traffic has worsened with urban sprawl. According to research published by the International Council on Clean Transportation (ICCT), on-road vehicles were responsible for nearly three-quarters of the transportation health burden in New Delhi in 2015.

To address peak-hour congestion, Delhi’s government reportedly plans to introduce a pilot congestion tax that would charge drivers who use select roadways during busy periods. Also known as congestion pricing, this aims to ease traffic and reduce pollution by discouraging unnecessary trips and encouraging drivers to use alternative routes, travel at off-peak times, shift to public transport, or share rides (and fees) with others. A 2010 study by the ICCT found that congestion tax schemes in London, Singapore, and Stockholm reduced congestion by 13%–30% and greenhouse gas emissions by 15%–20%.

This isn’t the first time Delhi has considered congestion pricing. Proposals in 2009 and 2018 failed to advance. Still, as Delhi looks ahead to its congestion tax pilot, I’ll highlight experiences from other cities that can provide valuable insights into how these schemes could be employed to effectively reduce traffic and air pollution.

Dynamic pricing

Delhi’s pilot would reportedly charge vehicles entering the city at 13 major entry points during morning and evening peak hours. With over 1.1 million vehicles entering and exiting daily, this makes sense, as such corridors are often heavily congested. A 2016 Centre for Science and Environment (CSE) cross-border traffic survey at nine major entry points to Delhi accounting for about 70% of traffic into the city found that the number of personal and passenger cars and two-wheelers entering daily was about the same as the number of vehicles registered in the city in a year.

At the same time, with over 1,800 new vehicles added to the Capital’s roads daily, an entry-point congestion tax during peak hours could miss an opportunity to address a large portion of daily vehicle emissions. Another CSE study estimated that the traffic at surveyed border points contributed just 10% of the total pollution loads emanating from the transport sector in Delhi. Administering taxes only at peak hours can also mean overlooking emissions during off-peak times, including those from heavy-duty vehicles, which are responsible for 20%–30% of transport sector pollution in Delhi and operate predominately outside of peak hours.

Other countries have sought to balance pollution and emission reduction aims against commuter access through dynamic pricing schemes that apply city-wide and have fees that rise at times of high congestion and drop during less busy times. In Singapore, an early pioneer in congestion pricing, charges are regularly reviewed and adjusted in response to changes in traffic patterns. Rates vary throughout the day and rise and fall gradually around periods of high traffic, which helps avoid surges before and after the designated peak hours.

Targeting the most polluting vehicles

Delhi reportedly plans to impose charges on most vehicles but exempt two-wheelers and electric vehicles. Congestion pricing programs in other countries have also provided discounts or exemptions for certain travelers, such as for residents of the designated taxation area, diplomatic vehicles, and emergency vehicles.

However, in Delhi, discounts and exemptions for any personal or commercial vehicle may risk undermining the core congestion and emission reduction aims of the schemes. For instance, two-wheelers, with reportedly about 1,100 new registrations  each day,  are roughly one in three vehicles on the road and are the second-largest contributor to transport pollution, according to The Energy and Resources Institute. Lessons can also be drawn from Delhi’s own 2016 odd-even scheme, which aimed to reduce pollution by restricting the operation of vehicles based on license plate number and exempted two-wheelers, women-only vehicles, and taxis, among others. Observers assessed that the program had minimal impact on pollution due in part to an increase in the use of exempted vehicles.

Pricing framework

Policymakers in other countries have wrestled with how to set congestion charges high enough to encourage reductions in vehicle use without placing a disproportionate financial burden on low-income travelers. In the 1970s, Singapore’s congestion toll led to a larger-than-expected drop in traffic that raised commuter welfare concerns. More recently, London revised its fee upward to maintain effectiveness in response to inflation.

There are other strategies. Currently, pricing in Singapore and Milan’s Area C varies by vehicle size and heavier, more polluting vehicles pay higher charges than lighter ones. This reflects their greater impact on both traffic congestion and pollution levels. Remote sensing, a method used to monitor real-world tailpipe emissions, could offer support for tailoring congestion prices to the emissions of different vehicles. This technology has been deployed in Europe, the United States, Spain, Sweden, and elsewhere to identify high- and low-emission vehicles and detect possible vehicle tampering. A recent ICCT study that took measurements via remote sensing in Delhi and Gurugram highlighted the difference between real-world tailpipe emission levels and laboratory limits and the need for advanced techniques for emissions monitoring.

A review of congestion pricing pilot programs in U.S. cities identified a number of possible approaches to mitigate the impacts of these schemes on low-income groups, including discounts, exemptions, and rebates. Such measures aim to minimize the financial burden on disadvantaged communities while maintaining the program’s effectiveness. Additionally, cities like Bogotá (Colombia) have adopted approaches that consider drivers’ income level alongside vehicle emissions to establish an equitable pricing structure.

The role of public transportation and supportive policies

Delhi has more than 7,500 buses in operation and over 390 km of metro connectivity, including links to other major cities. Still, challenges persist, including irregular bus frequency, overcrowding during rush hours, poor conditions of the bus, and last-mile connectivity issues for metro users. Ensuring that the public transit system is reliable, well-integrated, and equipped for last-mile connectivity through feeder bus services and pedestrian and cycling infrastructure is critical to realizing the shift away from private transport envisioned under congestion tax schemes. Indeed, congestion pricing was also considered recently in Bangalore and Mumbai, but it stalled due to concerns about the capacity of the public transport system to provide sustainable alternatives to private vehicle users.

Other cities have used revenues from congestion pricing to pay for upgrades to the public transit system. In London, the net revenue from congestion pricing has supported efforts to enhance bus fleets, expand bicycle and pedestrian lanes, improve road safety, and more. Cities like London, Paris, and Brussels have implemented scrappage programs that provide subsidies to retire older, higher-emitting vehicles and encourage a shift to public transit or cleaner private vehicles. Furthermore, initiatives like Delhi’s Mohalla bus scheme, a feeder bus service designed for neighbourhood-level operations, are expected to bridge the last-mile connectivity challenges by deploying 9 m zero-emission buses at scale.

In considering congestion taxing to help address poor air quality, Delhi has the opportunity to draw on global insights and establish a strong precedent for tackling traffic congestion and air pollution together. Success in this would promote sustainable urban mobility that offers a safer, healthier environment for its residents.

Author

Moorthy Nair
Associate Researcher

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