268 construction sites under scanner for failing to install pollution sensors

According to the data on the highest number of errant sites, 63 are in Rajouri Garden, 41 are in Greater Kailash, 38 in Kalkaji, 37 in Punjabi Bagh and 31 in Vasant Vihar, among other areas

The state environment department issued show-cause notices to operators of 268 construction and demolition (C&D) sites across the Capital for failing to install real-time air quality monitors, warning of shutting them down and levying environmental compensation if the needful is not done by the month-end.

Dense fog has exacerbated air pollution levels in Delhi-NCR. (Sunil Ghosh/HT Photo)

According to the data on the highest number of errant sites, 63 are in Rajouri Garden, 41 are in Greater Kailash, 38 in Kalkaji, 37 in Punjabi Bagh and 31 in Vasant Vihar, among other areas. These include both government and private sites.

“The idea behind registration was that the government could through these monitors track real-time data. At the same time, ground inspections could be carried out. Since these sites have not installed sensors since last year, a show-cause notice has been issued for failing to comply. If adequate action is not taken, they will be shut down,” an environment department official said.

Under the Graded Response Action Plan (Grap) Stage 2—currently in place in Delhi since October 22—all C&D sites having an area of 500 square metre and above are to share real-time pollution data with the government. Officials with the department, however, estimate that around 40% of 620 sites registered with the government have failed to install the sensors.

Under Stage 3 of Grap, private construction can be halted, and public projects can be halted under Stage 4.

Besides the larger sites, 523 teams were deployed across the Capital in September to monitor and assess dust norms at all sites, including those smaller than 500sqm in area.

Officials said dust from C&D sites and roads was a key reason behind high PM10 (particulate matter having a diameter of 10 microns or less) levels in winter. A source apportionment study by IIT Kanpur in 2016 showed that dust from roads, digging and agriculture accounts for the highest suspended particulate matter sources in Delhi, accounting for 38% of PM2.5 and 56% of PM10 in Delhi.

“This is why we have made it mandatory for large construction sites to also have anti-smog guns since 2022. Warnings are issued if the data is higher than permitted standards and suitable corrective action is not taken,” the official said.

Sunil Dahiya, founder and lead analyst at environmental think-tank Envirocatalysts said tackling each source of pollution was important, adding registration with the government will mean nothing if there is lack of transparency. “Action needs to be taken against sites that are not compliant. At the same time, this data should also be public on what the pollution levels at major sites are,” he said.