Inaccurate data, lack of real-time monitoring, and public transport shortcomings identified as key barriers to improving Delhi’s air quality

A recent audit by the Comptroller and Auditor General (CAG) has raised serious concerns over the Delhi government’s measures to control air pollution, particularly focusing on vehicular emissions, which have long been a major source of pollution in the national capital. The report, which was tabled by Delhi Chief Minister Rekha Gupta on Tuesday, outlines multiple shortcomings in the existing air quality monitoring system, public transport infrastructure, and enforcement of pollution control regulations.

One of the key findings of the CAG audit was that the locations of Continuous Ambient Air Quality Monitoring Stations (CAAQMS) in Delhi did not meet the requirements set by the Central Pollution Control Board (CPCB), potentially compromising the accuracy of the data generated. As a result, the Air Quality Index (AQI) values could be unreliable, impacting efforts to monitor and mitigate air pollution. The Delhi Pollution Control Committee (DPCC) also failed to provide the required air quality data for at least 16 hours a day, hampering the effectiveness of pollution control measures. Additionally, the report highlighted that the DPCC did not measure lead levels in the air, further undermining air quality monitoring.

The audit also pointed to a lack of real-time information on the sources of pollutants, with no studies conducted to track emissions from specific sources, such as different types of vehicles. Without this critical data, the government is unable to develop source-specific strategies for reducing vehicular emissions. The report also revealed that benzene levels—an air pollutant primarily emitted by fuel stations—remained higher than permissible limits at several monitoring stations, and there was no follow-up on the installation of a vapour recovery system at fuel stations, which could help mitigate these emissions.

On the public transport front, the report highlighted a severe shortage of buses in Delhi. While the city requires at least 9,000 buses to meet growing demand, only 6,750 buses are currently in operation. Furthermore, many buses are often off-road due to maintenance issues, and bus routes have not been rationalized to improve coverage. The report also noted that the number of Gramin Sewa vehicles, which provide last-mile connectivity, has remained stagnant at 6,153 since 2011, with many of these vehicles being over 10 years old and likely to contribute more to pollution due to poor fuel efficiency.

Despite these challenges, the Delhi government has failed to take action on alternatives such as monorail systems or “electronic trolley buses,” even though budget provisions for these initiatives have been in place for the last seven years. Additionally, the audit found that public transport buses were not subjected to mandatory emission tests twice a year as per the National Green Tribunal’s guidelines. Similarly, the required emission testing for Gramin Sewa vehicles was not consistently followed, with only half of these vehicles being tested for emissions during the 2019-2020 period.

Irregularities were also noted in the issuance of Pollution Under Control Certificates (PUCCs) to vehicles. The report found that in over 22 lakh diesel vehicles checked at pollution control centres between 2015 and 2020, emissions were not recorded for 24 per cent of vehicles, and in some cases, vehicles with emissions beyond permissible limits were still issued PUCCs. Furthermore, there were concerns about the integrity of the testing process, with multiple vehicles sometimes being checked simultaneously at the same centre or tests being completed in a suspiciously short amount of time, allowing for potential manipulation of the results.

The findings of the CAG audit underscore the urgent need for the Delhi government to address these systemic issues in its air quality management strategy. Despite the considerable investments made in efforts to control air pollution, the lack of reliable data, insufficient infrastructure, and poor enforcement of pollution standards continue to undermine the effectiveness of these initiatives, leaving Delhi’s air quality among the worst in the world.