In mid-November, 2016, smog in Delhi air reached its highest levels in 17 years, prompting the government to shut down 5000 schools for three full days, and calling on children to stay indoors. Following Diwali celebrations, parts of the city were reported to show pollution levels that were nearly 15 times the permissible limit. As against a permissible limit of 60 mg for PM 2.5, the count reached 999 mg per cubic metre during the early hours of the morning in several areas of the city (US Embassy-Delhi, 2016).
However, this is not a one-off phenomenon being faced by the national capital. Every year, in October, when the onset of India’s festive season coincides with a drop in temperatures, and the burning of crop stubble commences in the neighbouring states and the National Capital Region (NCR) turns into a gas chamber. Reason enough for India’s Supreme Court to admonish the authorities for their callousness (Wall Street Journal, 2016).
Factors contributing to Delhi’s smog
Delhi is located at 28.61°N 77.23°E. It borders Haryana in the north, west and south and Uttar Pradesh (UP) in the east. Two prominent features of the geography of Delhi are the Yamuna flood plains and the Delhi ridge. The Delhi ridge originates from the Aravalli Range in the south and encircles the west, north-east and north-west parts of the city. The neighbouring districts of Delhi are Ghaziabad and Gautam Buddha Nagar in Uttar Pradesh and Faridabad, Gurgaon and Sonepat in Haryana. The NCR covers an area of 1,484 sq km, of which 783 sq km is rural, and 700 sq km urban.
Since it borders the desert-state of Rajasthan to the south, wind speeds and direction can play a prominent role in blowing dust into the city.
Down the years, as population grew within Delhi, the NCR, which includes Noida (in Uttar Pradesh), Gurgaon and Faridabad (in Haryana) have experienced an increase of over 103 per cent with over 70 per cent increase only in the past decade (2001-2011) (Table 1). Within the city, population increased from 6.22 million in 1981 to 16.753 million in 2011 (Economic Survey of Delhi, 2012-13).
The number of registered vehicles in Delhi increased from 3 million in 2007 to 8.8 million in 2015 (Delhi Gov, 2015), amounting to a 193 per cent increase, resulting in increased vehicular exhaust. Road length, meanwhile, increased from 28364 km in 2001 to 33198 km in 2014 (Delhi Gov, 2014). Myriad constructions are simultaneously being put into place, such as flyovers, metro expansion and the like, increasing the city’s woes.
All this has resulted in a steady decline in ambient air quality in several parts of Delhi, with little improvement on the part of others (Table 2 & 3). PM 10 levels have shown a mixed trend, while one notices a steady rise in PM 2.5 levels.
In and around Delhi are numerous slums, with the poor openly burning firewood to stave off the chilly winter. This, along with the bursting of crackers to celebrate Diwali, and the burning of crop stubble in rural areas within Delhi-NCR and neighbouring states, contribute to a toxic soup to inhale for all Delhiites.
There are also other factors as scientist, Dipankar Saha, Chief of Central Pollution Control Board’s (CPCB) air lab points out, “Delhi has a disadvantage as regards its geographical location. It is landlocked with the Himalaya in the north, blocking the winds. The winds come from the south-southeast direction. When this stops blowing, there is a calm. This is a natural phenomenon every winter. This year, there was humidity intrusion. A combination of all these alongwith the burning of crop stubble created an unprecedented situation.” Besides the increase in population in NCR, Saha blames the disappearance of a buffer area around Delhi.
Source apportionment studies
Studies done for the CPCB by the Indian Institute of Technology (IIT), Kanpur using PM 2.5 as a marker pollutant found that the contribution of vehicles to ambient PM 2.5 concentration during winter and summer were 25 per cent and 9 per cent respectively.
In winter, 30 per cent of the pollution was from secondary particles, while 26 per cent was contributed by burning of biomass and 25 per cent by vehicles. In summer, soil and road dust contributed to 28 per cent air pollution, while coal and fly-ash contributed to another 26 per cent. Secondary particles contributed to 15 per cent, biomass burning to 12 per cent, and vehicles to 9 per cent of the pollution (Source).
As per the Emission Inventory, the top four contributors to PM 2.5 emission were road dust, vehicles, domestic fuel burning and industrial sources. Among vehicles, trucks contributed 46 per cent, while 33 per cent came from 2 wheelers and 10 per cent from cars—the diesel ones contributed 78 per cent while the petrol ones contributed 22 per cent to the pollution. Among the others, buses contributed to 5 per cent, light commercial vehicles 4 per cent and 3 wheelers 2 per cent.
Reacting to this data on construction and road dust, Saha says, “This problem started with the commonwealth games and the massive construction that was undertaken then, and is continuing even now. Also, cheaper Chinese fire crackers flooded the markets everywhere, and people indulged in their unrestrained use. With no winds and the intruding humidity, everything settled as a cap over the city this winter.”
Air quality monitoring in and around Delhi-NCR
NCR is a unique example of inter-state regional development planning including 22 other districts in the states of U.P, Haryana, and Rajasthan, with Delhi as its core. The NCR in India was constituted under the NCRPB Act, 1985. There are six cities around Delhi with operational ambient air quality monitoring stations (AAQMS) under the National Ambient Air Quality Monitoring Programme (NAMP) of CPCB. The findings are represented in Table 2.
Action on air pollution
Since the last few years, the government has taken a great deal of interest in curbing air pollution. Several high-level meetings have taken place, and norms have been issued by the CPCB to rein in atmospheric pollution. Meetings were called in November 2016 to chalk out an effective action plan on air pollution in Delhi. Discussions veered around short term and long term measures by the Delhi government to control air pollution, such as increasing the number of public transport buses in Delhi to bring down the total number of vehicles, and continuous monitoring of thermal power plants.
Other decisions involved action against visibly polluting vehicles, overloaded vehicles and vehicles parked in non-designated parking areas; strengthening of pollution-under-control (PUC) regimes; promotion of public transport system through expeditious expansion of metro rail and procuring of additional buses; sprinkling of water on dusty roads; introduction of wet/mechanised vacuum sweeping of roads, maintenance of pothole-free roads, black topping/pavement of road shoulders; greening of open areas of gardens and community places; closure of brick kilns using obsolete technologies in winter; strict implementation of dust control measures at construction and demolition sites; avoiding rampant onsite bitumen burning; strict enforcement of notified diesel gensets; and, setting up of bio-mass power plants in Punjab and Haryana to do away with the burning of crop stubble post-harvest.
The government of Delhi had also shut down Rajghat and Badarpur thermal power plants and confiscated about 900 kg of crackers. Diesel generator sets and construction activity were banned for around a week. The burning of garbage and dry leaves were prohibited with a Swachh Delhi App being launched to encourage the public to report any such cases.
To clear crop residue and prepare farms in the most cost affective manner after harvests, stubble burning is frequently undertaken. Labour and machinery are thus saved upon.
Since April, 2015, the Ministry of Environment, Forests and Climate Change has convened several meetings with environment ministers and officials of the neighbouring states and those whose territory fall within the purview of the NCR. Among various initiatives, a comprehensive action plan with short-term, medium-term and long-term targets was focussed on.
Total paddy straw generation in the Punjab is 19.7 million tonnes as per the State Government records. Punjab government is using 2.7 million tonnes of this which comprises basmati paddy straw for fodder. Since non basmati paddy straw cannot be used as fodder due to high silica content, 0.5 million tonnes is being sent to power plants as fuel and 0.15 million tonnes is being sent to factories for cardboard manufacturing. This leaves 15 million tonnes of paddy straw.
Punjab government has already taken up the distribution of equipment to manage crop residue so as to prevent farmers burning stubble. A happy seeder (machinery needed to pull out stubble) costs INR 1.30 lakh and can be used for 120 to 140 acres in a season. About 68,000 of such machines would be required to cover the entire area under paddy in Punjab. Punjab government has offered to bear 50 per cent of the expense and farmers are being convinced to bear the rest. A proposal has been sent for INR 1602 crores for straw management equipment to the Ministry of Agriculture with the rest INR 650 crore to be jointly provided by the State and the farmers.
As per Uttar Pradesh government’s official statement, 256 polluting industries adjoining the NCR were closed down between May to October, 2016. Registration renewal of 10 to 15 year old diesel and petrol vehicles has been stopped and all 1856 brick kilns shut down. The UP government is also subsidising happy seeders and other machinery by 50 per cent to help prevent stubble burning. Fines have also been instituted for stubble burning.
In Haryana, which has 22 districts in NCR, all brick kilns have been shut and vacuum machines are being used to control the pollution in HUDA and all municipal areas. Burning of paddy straw has been prohibited by Haryana and action has been instituted for all 17 polluting industries identified by the CPCB. The Haryana State Application Centre has also been engaged to provide satellite imagery on the level of pollution by the Haryana government.
There are various solutions cited, but as always, we have fallen short on implementation. Incidentally, although IIT, Kanpur had submitted its study and recommendations in January 2016, the measures suggested were not implemented (The Scroll, 2016). It was ironical that there were no discussions for nearly an year, and emergency measures like shutting down of schools, banning the burning of garden waste and diesel generators were taken as last minute interventions when matters went out of hand. In fact, if this had been done at the beginning of the year, Delhi would have been spared its present agony. The IIT had put forth 28 measures to be implemented over 7 years, 17 of which were to be implemented immediately. Going by the study and statistics, these could have brought in improvement anywhere between 30-100 per cent in the air, averting the present calamity.
An estimated 5 lakh cars are added every year on Delhi roads. This is despite the city boasting one of the best metro services in India, besides a large fleet of buses. Delhiites prefer driving down to work, rather than opting for public transport. This is because of lack of last-minute connectivity to metro stations and the like. If the bus network were expanded to cover every corner of the city, Delhiites would be sure to avoid burning fuel. Walkways could be another solution, wherein people could easily negotiate the distance from their homes to the nearest bus or metro station without fearing being crushed by the city traffic. Since vehicular exhaust is a problem the year round, solar or electric vehicles could be promoted in place of polluting petrol or diesel ones.
But above all, there is an urgent need to educate policy makers about the need for enabling a ‘green’ lifestyle. After all, the police have limited space for impounded vehicles—and collecting fines for garbage fires and dust violations is clearly no long-term solution. The odd-even rule imposed by the Delhi government too, met with limited success.
This year, concrete steps have been taken by the authorities to tackle the wintry smog, following the worst pollution in 17 years’ time.
“But unless long-term solutions accompany emergency measures, there can be no solution to the Delhi smog problem”, points out Anumita Roychowdhury, Executive Director, Research and Advocacy, Centre for Science and Environment (CSE). “There is also a need to issue alerts on a regular basis along with the health advisories that are being currently put out with the air quality data”, she adds.
Economic Survey of Delhi, 2012-13. Available at:
India Today. 2016, NGT Poses 5 Questions on Pollution, Delhi Government Draws a Blank.
The Scroll. 2016. Delhi Government is Crowd-Sourcing Pollution Solutions – Which IIT Had Given it Months Ago.
The Times of India. 2016, Delhi a Wake-up Call for World on Air Pollution: UNICEF.
The Wall Street Journal. 2016. Smog in Delhi Tests India’s Ability to Change.