Construction sites to get pollution colour codes
Delhi’s environment department has prepared a colour-coded four-stage warning system for all construction and demolition (C&D) sites in the Capital with an area of over 5,000 sqm, in a bid to control local sources of dust and air pollution, officials aware of the development have said.
The department, in a review meeting held on March 27, informed the Commission for Air Quality Management that it has asked all C&D sites with an area of over 5,000 sqm to install real-time air quality sensors, the data generated from which will be transmitted to Delhi Pollution Control Committee (DPCC).
It added if PM10 levels rise beyond permissible limits, SMS alerts will be immediately sent to the construction site.
The warning system, based on colour codes — yellow, orange, red and purple — will allow DPCC and environment department to take action, which includes warnings, fines and eventual closure of the site itself, the officials said.
PM10 are solid particulate matter with diameters of less than 10 microns, which can easily enter the lungs and bloodstream and cause serious ailments. While PM 2.5 pollution is largely associated with combustion sources, PM 10 largely comes from dust.
According to data collected by the environment department, Delhi has 611 active C&D sites registered with the Delhi government, of which 329 are sharing real-time air quality data. An environment department official said the target is to bring the remaining 282 sites under realtime monitoring too, following which this colour-coded system will be formally implemented.
“We have asked the remaining C&D sites to install them before the coming summer. This will allow all sites to be monitored remotely,” said a senior environment department official on condition of anonymity.
Data gathered by the environment department shows that of the 282 sites, the highest concentration was in Rajouri Garden, where 63 such sites exist, followed by Greater Kailash (41), Kalkaji (38), Punjabi Bagh (37) and Vasant Vihar (31).
“These areas have the higher density of active construction sites (within a 3km range) that are not uploading their air quality data at the moment,” the report shared with CAQM said.
The official quoted above said, “Based on the data, SMS alerts will be sent to the sites, informing them that their levels are exceeding permissible norms. If PM10 levels are beyond permissible levels on multiple occasions, a formal warning will be issued via SMS, and if corrective action is still not taken, then a physical inspection will be done, along with a possible fine. The site can also be shut down.”
The official said in the first or yellow stage, if PM 10 levels are 20% higher than the threshold of 100µg/m3, then an auto-generated SMS will be sent to the builder. This will escalate to second or orange stage if four yellow alerts are issued within one week, with another SMS to be sent to the builder, seeking immediate corrective action.
If four orange alerts are issued in 30 days, then the C&D site will be placed under third or red stage, where an official warning letter will be sent to the site. Under the red stage, the site will also be required to identify local sources impacting air quality.
If an action report is not submitted within three days, the plan states that the site will then be placed in the fourth or purple stage, which will require a physical inspection by DPCC, with all pollution-intensive activities to be stopped immediately. Sites can be shut down in the purple stage, if adequate corrective action is not taken, or violations are large-scale, officials said.
Dipankar Saha, the former head of Central Pollution Control Board’s air laboratory, said dust, which leads to a spike in PM10 levels, is among the primary sources of pollution during summer, requiring focused action. “The plan should help pinpoint sites leading to local air pollution. It is also important to look beyond C&D sites and ensure dust is controlled at the neighbourhood level too,” he said.