Chennai vehicles pollute nearly as much as Delhi's: CSE data

If Delhi’s pollution data scares you, you should also be equally informed and alarmed about the air quality in Chennai.

Published: 11th February 2020 08:08 AM  |   Last Updated: 11th February 2020 11:48 AM   |  A+A-

Chennai Pollution

For representational purposes (Photo | EPS)

Express News Service

ALWAR: If Delhi’s pollution data scares you, you should also be equally informed and alarmed about the air quality in Chennai.  

Chennai has the second-worst record of vehicular pollution in India after Delhi, generating 3,200 tonnes of carbon dioxide (CO2) per day, a primary greenhouse gas, according to Centre for Science and Environment (CSE).

This was revealed from the data compiled and analysed by CSE, a research organization, which published a study report titled ‘The Urban Commute’, which ranked 14 Indian cities. 

Besides CO2, Chennai generates over 1,000 kg of particulate emission load per day and 12,000 kg of nitrogen dioxide per day from urban commuting, which again are second and fourth-worst in the country.

 CSE researchers said the study involved reviewing and assessing the data available on how people commute in the cities. This does not involve freight movement in the cities. 

The critical parameters that have been considered to understand the difference across cities include level of motorisation, volume of travel demand based on population, share of different modes of transport in meeting travel demand (public transport, walking and cycling, and personal vehicles), average distances in cities, average length of daily travel trips, and the quality of vehicle technologies and transport fuels.

Based on the results of this analysis, the 14 cities have been ranked to see which ones pollute the most. Another study also points out a significant drop in the public transport ridership across various cities including Chennai. 

‘Vehicle registration data is not always updated’

“An analysis of this kind is not easy in India, as the Central and State governments do not have established protocols to survey and create databases on commuting practices in cities. The only data that is maintained is that of the vehicle registration, which is not always corrected or updated on the basis of obsolescence, retirement and phase-out. At times, data has to be mined from the detailed project reports for metro and other infrastructure projects or other city-level studies,” says Anumita Roychowdhury and Gaurav Dubey, authors of the study.

Sayan Roy from Clean Air and Sustainable Mobility Team of CSE told Express that there is another study being carried out on public transport ridership, where the analysis shows a significant drop across various cities, including Chennai. 

There is limited academic research that gives an idea of some indicative trends. One older estimate by the Indian Institute of Technology, Kanpur, has projected that the overall share of public transport will decline significantly in the years to come, while that of personal vehicles will increase.

The share of public transport is projected to decrease from 75.7 per cent in 2000-01 to 44.7 per cent in 2030-31, whereas the aggregate share of private and para-transit modes is projected to increase from 24.3 to 55.3 per cent during the same period.

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