This means that vehicle owners need to pay extra to enter the busiest and most congested parts of the city, and we have already identified 12 such hotspots in Delhi.
From media reports, it is observed that the Delhi government, the National Green Tribunal (NGT), the Central Pollution Control Board (CPCB), the Supreme Court-appointed EPCA (Environment Pollution Control Authority), governments of adjoining states (Punjab, Haryana and Uttar Pradesh, and their pollution control boards) are all showing alertness in fighting air pollution in the Capital well in time. Now, the real test lies in coordinating their actions for implementation of various measures. The challenges are already known based on our experience of last many years.
Air pollution in Delhi is contributed by the presence of PM 2.5 and PM 10 particles, carbon dioxide, carbon monoxide, nitrogen oxides, sulphur dioxide, garbage dumps and landfills containing plastics, etc. The main sources of all this are (1) transport system, (2) construction/demolition activities, (3) road sweeping, (4) coal-fired power plants and brick-kilns, and (5) most importantly, rice stubble burning in the bordering states in the months of October and November every year.
Let me first discuss the existing scenario of stubble burning this winter, as it is a major contributor to air pollution as usual. According to scientists at NASA, there may be spikes in farm fires this winter. It is because their satellite images suggest that crop harvest in Punjab and Haryana this year may be at the historical highs because of monsoon staying longer and some local factors. Consequently, much more paddy straw—about 200 lakh metric tonnes—is likely to be generated, increasing farm fires. Here, it may be noted that 1 tonne of stubble releases 2 kg of sulphur dioxide, 3 kg of particulate matter, 60 kg of carbon monoxide, 1,460 kg of carbon dioxide and 199 kg of ash. Just imagine the havoc burning 200 lakh tonnes will do.
NASA has found this in advance by calculating what is called the normalised difference vegetation index (NDVI)—a measure devised for greenness that can indicate crop or vegetation cover. Further, NASA data shows that between 2002 and 2018, the most number of stubble burning cases reported were in 2016, at 18,000. This year, we expect the figure may be 16,000 or so, but fearing detection by satellites, farmers may light fire in small pockets not caught by satellites.
According to a recent CPCB report, the annual average of PM 2.5 levels during 2016-18 (at 115 micrograms per cubic metre, which is three times the safe limit prescribed by the WHO) is 25% lower than the average during 2012-14. However, Delhi’s average level needs to be lower by 65% to meet the standards under the National Clean Air Programme (NCAP), which is a long way to go.
The government of Delhi has introduced a number of measures during the last few years but without any real respite from air pollution. In view of this, it is necessary to review the various steps taken by the government to increase their effectiveness. The main ones are as under:
There are certain guidelines for agencies while carrying out construction work, for avoiding and controlling dust, but these are not being strictly followed.
Using mechanical road sweeping machines is a must to bring down dust. It is observed that four civic bodies (having, among them, 56 such machines) are not effectively utilising their machines primarily because of poor maintenance due to non-availability of spare parts.
The average road length swept currently is 38 km per shift of 8-10 hours, instead of the road length of 80-100 km per day according to a study by TERI. Dumping of dust collected by machines (a machine collects 1.13 to 4.1 tonnes per shift) is another problem that needs to be fixed soon.
Reduce stubble burning sufficiently in adjoining states by increasing awareness amongst farmers and providing happy seeders for sowing and other necessary mechanical devices through necessary financial incentives.
Measures like staggered office timings, banning diesel gensets and shutting down of industrial units based on coal and biomass and brick-kilns during winter is not being resorted to.
Besides the above, it is suggested that the following long-term measures to combat the menace of air pollution, which, in course of time, may engulf many more cities in India, be taken:
Planting of saplings should be done in very large numbers to compensate for highly reduced green cover over a period, and don’t cut trees in the future. These are our greatest carbon sinks, along with water bodies and soil.
Increase the number of public transport buses drastically. In fact, during the last 10 years, the number of buses has gone down to 5,500 from 6,329, while we need 11,000 buses to meet the demand and also increase dependence on public transport to reduce air pollution.
Cloud seeding and artificial rainfall can play an important part in bringing down air pollution. It is heartening that IIT Kanpur has been awarded a project by the CPCB in this area.
Install gigantic air purifiers, and it is now learnt that the National Environmental Engineering Research Institute (NEERI) is working on a variant of WAYU that caters to 500 sq-m.
Introduce congestion pricing. This means that vehicle owners need to pay extra to enter the busiest and most congested parts of the city, and we have already identified 12 such hotspots in Delhi. Singapore, Stockholm and London are doing this. The recent RFID system (introduced by the School of Planning and Architecture) for commercial vehicles entering Delhi is an example of congestion pricing that has worked.
Innovative ideas like creating vertical gardens on all public buildings/spaces (like in Singapore) to replace the greenery lost on the ground, and providing water sprinklers behind all two-wheelers are being suggested and the feasibility of these may be examined sincerely.
To conclude, intensive ground monitoring and the implementation of the above measures is key to combating air pollution in Delhi NCR. We should be fully ready to execute the Graded Response Action Plan of the EPCA in letter and spirit.