NCR cities will get more stations to monitor pollution

AIR WE BREATHE Nearly 60% of the country’s urban areas and the entire rural belts are still off the monitoring radar

NEWDELHI: The Central Pollution Control Board (CPCB) plans to expand its existing network of air quality monitoring stations in the national capital – both real time and manual – from 89 to 141.

Once the plan is implemented, the four NCR cities – Gurugram, Noida, Faridabad and Ghaziabad – will get at least five additional monitoring stations.

But with 60% of the country’s urban areas and the entire rural belt still off the radar of the pollution monitoring network, experts said real-time low-cost sensors are key to air pollution monitoring in the future.

Arun Kumar Mehta, additional secretary of the Union environment and forest ministry, said, “We need workable data even if it is not 100% accurate. Low-cost real-time sensors can achieve this. We need to expand our monitoring network to check pollution levels in smaller towns and rural areas. That can’t be done only with sensors that can give accurate data but are very expensive.”

Mehta was speaking at a workshop organised by the Union environment ministry and IIT Kanpur to discuss the potentials and challenges of low-cost sensors – an emerging technology – on Wednesday.

SN Tripathi, coordinator of the Centre for Environmental Science and Engineering at IIT Kanpur, said, “As part of a pilot project, IIT Kanpur had installed 20 low-cost sensors in Delhi between November 2017 and March 2018. The sensors performed well and gave some interesting data, which are being analysed. They didn’t require any calibration for at least four months. With proper calibration and battery life, low-cost sensors can fill up the existing data gap in India.”

While the cost of conventional monitoring stations can run up to ₹5 crore, the cost of real-time sensors can be as low as ₹5 lakh or even less.

The paucity of funds is one of the main challenges in setting up conventional high-cost monitors across the country.

“Monitoring air quality across India would require huge resources. So we need alternative solutions. Solutions that may not be the best but are workable,” said CK Mishra, union environment and forest secretary.

A study – comparing pan-india district level data on PM2.5 levels over the last two decades -- conducted by the IIT Delhi recently has shown that the rate of increase in pollution levels in smaller towns such as Gorakhpur, Muzaffarpur and Jabalpur are way higher than that of metropolitan cities such as Delhi, where pollution levels are stagnating.

Currently, there are 134 realtime air quality monitoring stations in 71 cities across the country. Of the 134, NCR has 52 stations and Delhi has 38 stations, thereby revealing the gap in air quality monitoring in the country. Experts have suggested that a two-layered monitoring network – comprising both high-cost monitoring stations that can provide accurate data and low-cost real-time sensors – could be used to cover the entire country.

Existing automatic air quality monitoring stations in DelhiNCR

Delhi UP Haryana Rajasthan