Mumbai’s air quality info inaccurate since Saturday

Recent air quality information regarding particulate matter (PM) for Mumbai has been inaccurate as most pollution monitoring stations of the state pollution control

Recent air quality information regarding particulate matter (PM) for Mumbai has been inaccurate as most pollution monitoring stations of the state pollution control board are not operational. The Central Pollution Control Board’s (CPCB) daily bulletin on Monday and Tuesday is collating AQI data from only five stations since April 11.

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There are 12 air quality monitoring across the Mumbai Metropolitan Region that record PM2.5, PM10 among other pollutants on a real time basis. All except one in Kalyan, which has been inoperative throughout the lockdown, were functioning normally till April 11. Since then, data from only three PM 2.5 monitors and five PM 10 is being published on the Maharashtra Pollution Control Board (MPCB) website. The reason for the failures at the other stations is not known.

“Even though these are continuous monitoring stations, in the event of a power trip or technical glitches, our officers go to these stations for a simple reboot. However, this is not happening due to current restrictions. We will be requesting the government to allow these activities to resume for the benefit of citizens,” said SC Kollur, chief scientist, MPCB. Monitoring stations are not listed under essential services in Maharashtra.

Consequently, the air quality index (AQI) being generated for the region does not have data from stations in Worli, Colaba, Vile Parle, Borivli, Sion, Nerul, Kalyan and Vasai. “Having temporal gaps makes it difficult to correctly evaluate the effect of the lockdown on the city’s air quality,” said independent researcher Ronak Sutaria.

Based on data collected from all stations other than Kalyan, between March 23 and April 8, Mumbai witnessed a 65-70% decline in air pollution during lockdown, said Kollur.

The overall air quality index (AQI) on Tuesday in Mumbai was 70 (satisfactory), according to the System of Air Quality Weather Forecasting and Research (SAFAR), which has 10 monitoring stations across MMR. Navi Mumbai recorded high PM 2.5 levels with AQI at 120. Gufran Beig, director, SAFAR, said PM 10 levels were marginally higher and explained this as “seasonal phenomenon”.