‘Kol roads least congested but most polluted among all metros’
Times of India | 10 February 2026
Kolkata: The city has emerged as the least congested among India's metropolitan cities, according to a recent study by the Centre for Science and Environment (CSE). However, Kolkata has the highest exposure to vehicular air pollution among India's major cities.
The finding is largely attributed to its weakened yet still dependable public transport system, which continues to absorb a significant share of daily travel demand.
The study ranks Kolkata with the lowest congestion index among megacities, measuring the percentage drop in average vehicle speeds between lean and peak hours. During lean hours, vehicles in Kolkata travel at an average speed of 32.6 kmph, slowing to 18 kmph during peak hours — a congestion index of 38.9%. This is lower than comparable figures for Mumbai, Chennai, Bengaluru and Hyderabad. Keeping Delhi aside, Kolkata also records the second-highest average peak-hour speed among major metros, underlining the continued relevance of mass transit.
Peak hours in Kolkata often resemble a slow-moving parking lot. Autos, private cars, two-wheelers and buses compete for the limited carriageway, while on-street parking frequently occupies one-third to even half the width of roads. "Congestion in Kolkata is shaped as much by city design and parking practices as by traffic volume," said CSE executive director Anumita Roychowdhury.
Vehicle ownership, however, is rising sharply. Between 2016 and 2024, registrations of four-wheelers increased five-fold while the number of two-wheelers surged more than 12-fold. Despite this growth, car trips account for only 5.3% of all journeys.
Kolkata's travel behaviour has also evolved. The average number of trips per person per day has risen from 1.5 in 2001 to 1.8 in 2025, while average trip length has fallen from 8 km to 6.5 km. Importantly, 56% of trips in Kolkata are still within a 5km radius.
Yet, the report highlights a troubling contradiction — it has the highest exposure to vehicular air pollution. According to CSE, this paradox stems from heavy dependence on road-based transport, limited road space and massive parking blocks, rather than sheer vehicle ownership alone. Moreover, weakening public transport is leading to a steeper increase in personalised vehicles.
To tackle pollution and future congestion, CSE called for an urgent revival of Kolkata's tram network — India's only operational tram system and the city's original zero-emission mode of transport. The report argues that trams, combined with electric buses, low-emission zones and expanded walking and cycling infrastructure, could deliver both cleaner air and smoother traffic. The study also recommends curbing personal vehicle use through parking management, variable parking pricing, congestion charges and road pricing.