Editorial: Lost again in the winter smog

As widely feared, air quality in New Delhi worsened the morning after Deepavali with at least 20 monitoring stations across the national capital reporting PM 2.5 pollutant levels in the ‘Severe’ (400+) category.

Several other cities in the north also recorded ‘Very Poor’ (301-400) air quality, reflecting the common environmental conditions predisposing the entire Indo-Gangetic plain to air pollution during the winter months. In fact, November 8 was the fourth most polluted day thus far this year in Delhi and the fourth most polluted Deepavali day since 2016.

These are disappointing outcomes considering that the Delhi administration had rolled out several pre-emptive measures to avoid the anticipated post-Deepavali spike in pollution this year. By November 8, the city was placed under Stage III of the Graded Response Action Plan (GRAP).

Accordingly, office hours were staggered, work-from-home options were mandated, and older motor vehicles were barred from operating in Delhi. To mitigate dust and industrial pollution, non-essential construction and demolition activities were prohibited across the national capital region. Locally, authorities deployed water sprinklers, anti-smog guns, and mechanical sweepers along major traffic corridors and at pollution hotspots. Authorities intensified monitoring of open garbage burning and biomass combustion. Public transit was boosted by scheduling additional daily Metro trips and deploying extra electric buses.

On the face of it, they were a fairly comprehensive set of measures. But they do not seem to have made a significant difference to the post-Deepavali pollution spike. Delhi recorded an average Air Quality Index (AQI) of 368-373 (‘Very Poor’) on festival night, escalating to 483 (‘Severe’) at several locations on the morning after. In fact, Deepavali night readings were the highest since 2022.

This suggests that measures taken with a perspective of weeks rather than months have had limited impact and that deeper, tougher, and more permanent correctives are called for.

The bad air problem of cities in the Indo-Gangetic plain is the result of unfavourable meteorology compounded by several man-made contributions—such as farm stubble burning, vehicular exhaust, industrial pollution—each of them significant but not singularly preponderant. For instance, vehicular emissions contribute 20-25% to the annual PM2.5 pollutant load in Delhi, followed by biomass and stubble burning (15-30%), road and construction dust (10-15%), industrial activity (10-14%), and municipal waste burning (5-8%). Firecrackers add an annualised 1% over a 48-hour window, producing the classical Deepavali spike.

Any set of corrective measures must attack all of these factors, not one or two that are politically feasible. Further, these measures must be in force for months and years, not days or weeks. If their scope is limited to municipal jurisdiction, with no participation by multiple agencies, they are bound to fail.

It is time we realised that Delhi’s air pollution is not going to be solved through administrative action. What it needs is a policy coherence in which pollution is recognised as a public health issue, not merely an environmental concern. As a knowledge paper brought out by FICCI last week says, the situation calls for close collaboration between state and central governments, industry, and healthcare providers across several long-duration initiatives to achieve measurable improvements in public health. If the purpose is only to bring down the post-Deepavali spike from ‘Severe’ to ‘Poor’ levels, just so we avoid bad press for a few days, then we have already failed.