Delhi pollution: 'Emergency measure' launched, smog towers' efficacy questioned

Experts have pointed to the limited ability of the smog tower, saying they can reduce pollution only to a certain extent. Delhi recorded oner of the poorest AQIs on the morning after Diwali.

The Delhi government on Saturday banned 92 construction sites for violating norms and started spraying water on roads a day after the national capital's pollution level rose to alarming levels. According to government data, Delhi's air quality index (AQI) nosedived to the 'severe' category, measuring 533 on Saturday morning, two days after Diwali.

An anti-smog water tank spraying water on roads of Delhi on Saturday. (ANI Photo)

"As an emergency measure, we've started spraying water on roads with the help of anti-smog water tanks to reduce the air pollution. We've also banned 92 construction sites for violating norms," news agency ANI quoted Delhi environment minister Gopal Rai as saying.

And in more worry, many areas in the national capital recorded an AQI of over 600, making the ambient air unsuitable for breathing. The numbers were released by the Dephi Pollution Control Committee (DPCC), based on data from the smog towers installed in the city.

The huge structures, believed to provide clean air to nearby areas where they are installed, failed to deliver. The smog tower in Connaught Place could only reduce the PM10 level from 649 micrograms per cubic metre to 511 micrograms per cubic metre, as per the readings taken at 9 pm on Thursday, the night of Diwali.

It recorded a PM2.5 concentration of 642 micrograms per cubic metre at the inlet and 453 micrograms per cubic metre at the outlet on the same day.

The safe limit for the lung-damaging fine particles PM2.5 and PM10 is 60 micrograms per cubic metre and 100 micrograms per cubic metre, respectively.

Experts have pointed to the limited ability of the smog tower, saying they can reduce pollution only to a certain extent.

"This experiment at Connaught Place has shown that smog towers can never be a solution to the problem of air pollution. Any further wastage of money on such structures should be stopped immediately. The money should be utilised to reduce pollution at source," said Sunil Dahiya of the Centre for Research on Energy and Clean Air.

Chief minister Arvind Kejriwal had inaugurated the smog tower on August 23 which, officials say, can purify air in a one-km radius around the structure at a rate of around 1,000 cubic metres per second.

There is no reaction from the Delhi government about the efficiency of the smog towers.