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Why Delhi’s Plan for Air Filters at Traffic Intersections is a Red Herring

Why Delhi’s Plan for Air Filters at Traffic Intersections is a Red Herring

The setting sun over Connaught Place, New Delhi. Credit: wili/Flickr, CC BY 2.0

Installing an air filter in public is more like avoiding the problem and diverting attention away than solving it. Emissions should always be controlled at the source.

The setting sun over Connaught Place, New Delhi. Credit: wili/Flickr, CC BY 2.0
The setting sun over Connaught Place, New Delhi. Credit: wili/Flickr, CC BY 2.0

New Delhi: The first sentence we hear in an introduction to air pollution is that it knows no boundaries – unless you build a wall around it. Then again, even the great wall of China is incapable of holding back the interaction of pollutants between China and Mongolia – both of which, along with India, have the most polluted cities in the world according to the WHO. The situation in Delhi, where the conversation on air pollution has been peaking because of Diwali celebrations, additional factors like agricultural clearing by fire in the Indo-Gangetic plain, slowing wind speeds, curling north-westerly winds, dropping temperatures (necessitating the need to burn some more wood and coal to keep warm) have exacerbated the problem. At this juncture, the Delhi Government has just announced that it will install air filters and mist fountains at traffic intersections to make the air cleaner.

Imagine a sci-fi dystopia wherein the world’s pollution has breached all kinds of limits and people are walking around with glass jars and clean-air tanks on their backs; sitting in their offices or homes, where every cubic meter of air is filtered of all harmful pollutants; or even a big bubble covering a cricket stadium where the air is filtered for all to enjoy the game. All these scenarios have one thing in common – the volume of air under consideration is confined and under full control of the user or the operator. There is one inlet for air, through the filter, and the outlet is into the glass jar, the room or the stadium; not to a traffic intersection where the flow of air is not in anybody’s control.

This is not the first time Delhi has experimented with this idea. Before the Commonwealth Games in 2010, an Italian company installed a $300,000-air-filter in Connaught Place, claiming it to be the cleanest spot in Delhi. There are no numbers to back this up, except for the 2.5 kg of dust collected during its one month of operation. Our estimate for Delhi’s particulate matter pollution is approximately 60,000 tons per year, not including seasonal dust storms and agricultural-clearing emissions. That is 5 million kg per month. Assuming that Connaught Place was the cleanest because of the filter’s operations, we would actually have needed at least 2 million of them to cover the city.

A wise decision was made to curb that idea. We cannot control pollution where we breathe. However, in 2016, with the government’s intention to install air filters and mist fountains at traffic intersections, one is pressed to question the logic at play here. If we could suck up pollution on the roads, then why worry about emission and fuel standards? What difference does it make if the vehicle is one year old or 10 years old, if the vehicle is running on diesel, petrol or CNG? If the vehicle is Bharat-IV compliant or Bharat VI? What difference does it make if the waste is burnt or packed at the landfills?

Being able to control pollution by sucking out and filtering the dirty air will lead nowhere. In addition, here are eight common myths about air pollution in Delhi that are unlikely to ever contribute to a long-lasting solution.

  1. Awareness that Delhi is the most polluted city in India. The fact is that Delhi is the most studied and the most documented city on air pollution issues. Almost all the national as well as international agencies want to work in Delhi. The city has the most number of air-pollution monitors operated by multiple agencies, including the emerging non-regulatory low-cost monitors. So, with most coverage, it has obviously become known as the most polluted city in the country. If data from other cities can be as freely documented and disseminated at the same scale, this could be different.
  2. Most of Delhi’s pollution comes from outside Delhi. Somehow, that air pollution knows no administrative boundaries becomes suddenly applicable here and Delhiites become more willing to point fingers at their neighbours. This is partly true – particularly when there is a dust storm coming in from the Thar desert or the Middle East (common occurrences in April and May) and during the agricultural-clearing season in Punjab and Haryana (common occurrences in November). Other than that, everything is very much local. The media usually starts talking about air pollution in late October and November as the agricultural clearing peaks. For the same reasons, we simply assume all our pollution, all year long, comes from outside Delhi.
  3. We need more studies to ascertain where the pollution is coming from. As a scientist, I agree, we need more studies – to enhance our understanding. However, we do know most of the sources to act now. Consider any 2-3-km-wide block in Delhi and you are likely to find residential cooking and heating, waste burning (it is banned only on paper), some form of industrial activity, diesel generators, vehicles and associated road dust, construction activities – all low-lying sources that contribute to local pollution.
  4. Transport is the biggest contributor to air pollution in the city. The Central Pollution Control Board released one report in 2010 that put transport contribution at under 20%. The Delhi Pollution Control Committee released one report in 2015 that put transport contribution at under 25%. Both were conducted by the same team, at IIT-Kanpur. This means up to 75% of the pollution is from non-transport sources. This is a classic case of “what we see is what we believe in”. We are stuck in traffic for a few hours a day, moving at 15 km/hr, with an engine under the hood that can go at 100 km/hr and we start blaming transport for all air pollution problems. Transportation’s contribution must be cut – but we shouldn’t be neglecting other contributions along the way.
  5. The odd-even pilot was good for mitigating air pollution. The average commute speeds in the city went up but no statistically significant change could be monitored for air quality. We missed the bus here: the goal is to cut the demand for personal transport, not target individuals with cars. Take Hong Kong or Singapore, example: both cities managed to cut down the demand for personal transport by setting up a very wide network of public transportation systems (road and rail), walkways and bikeways, and promoted them aggressively. They also have economic measures in place, such as higher vehicle sales and congestion taxes that further enabled the move from personal to public modes of transport. All this was possible only because the alternatives were in place – more buses and inter-connectivity via rail, walkways and bikeways. The odd-even policy was, and is, a good policy but for the level of infrastructure in Delhi, this will remain an experiment. If we want this move to be permanent, irrespective of whether someone owns a car/motorcycle or its registration number, we need a safe and clean infrastructure that will move people from point A to point B using rail, bus, bike and walk – and eliminate the need for personal transport. The Delhi Transport Corporation operates approximately 6,000 buses but the city could use at least 15,000.
  6. There is a silver bullet to control pollution. This is a long term game and history tells us that this fight was not easy – neither in the EU nor in the US. Today, countries like India and China are better placed in terms of there being examples to look up to, lessons to take home from the EU’s and USA’s experiences, and the technology to control pollution is far superior than what was available in the 1980s and 1990s. If anything, the challenge is now in convincing policymakers to learn from the past and act fast. In India, we are seeing changes in some sectors, such as new emission standards for coal-fired thermal power plants, accelerated introduction of cleaner fuel for the transportation sector, promotion of liquefied petroleum gas and incentives for better industrial efficiency. These are good global measures that will take some time to trickle down. But more importantly, the faster we act on implementing these developments, the faster we will move towards having cleaner air.
  7. Installing more monitors to control pollution. Measuring pollution is not controlling pollution. Nonetheless, official statements continue to claim this step of air quality management as a control strategy. Though we do need more data and nothing beats an informed decision, generating information is not controlling pollution.
  8. Pollution can be controlled with air filters. This is more like avoiding the problem and diverting attention away from the problem than solving it. Emissions should be controlled at the source. If you are in a room with one door, it makes perfect sense to filter the air; but what sense does it make if there are no walls altogether?

Spending money wisely

The city has been collecting environmental tax and additional sales tax on diesel vehicles, challans during the odd-even experiment, etc., all pooled into a ‘green fund’. According to the Environment Pollution Control Authority, nearly Rs 100 crore was collected as environmental compensation charges between November 2015 and February 2016. One can only assume that this fund was close to Rs 400 crore in October, 2016, pushing the Delhi government to take desperate measures to spend it. Thus, air filters and mist fountains at traffic intersections?

According to the Maharashtra Pollution Control Board and the National Environmental Engineering Research Institute, their trail cost of operating an air filter, one of which is to be installed in Delhi, was Rs 20 lakh, with an operating area of 1,250 to 2,800 sq. m. Delhi’s administrative area is 1,500 sq. km with roads covering about 15% (approx. 225 sq. km). Let us assume that the Delhi government is procuring 1,000 air filters at about Rs 200 crore (plus operational charges) to cover an operational area of 1.2 to 2.8 sq. km. You do the remaining math.

Apart from the ill-logic of installing air filters, the proposal also lacks clarity on basic practicalities. For example: How many intersections will be covered? How often will the filters be changed? Which agency will be responsible for their maintenance? What is the budget of this program? How long will it run for? Will it be a pilot for two or three weeks like the odd-even programme was? Are we going to measure ambient air quality at these intersections to quantify effectiveness? And, more importantly, will that data be  available in the public domain (during operations and after)? That last bit is important because the Delhi government apparently operated more than 75 air quality stations during the odd-even experiments but none of that information is in the public domain – nor has it been submitted to the National Green Tribunal. If there is no transparency in the process from the beginning, this effort will remain a red herring.

If money is indeed available for air quality management, here are some suggestions:

  1. Delhi conspicuously lacks a good continuous air quality monitoring network. The Delhi Pollution Control Committee operates six monitors, of which two do not measure PM2.5. Moreover, a recent data analysis put the data collection at 29%. There are other groups operating stations but their data is not available publicly. For a city covering 1,500 sq. km, four monitoring nodes with 29% annual data collection efficiency does not imply a good database at all. The city needs at least 50 continuous monitoring stations, delivering data 24×7, with full access to the archives for everyone to see. The average cost of such a monitor is Rs 1 crore, with 10% operational costs every year. So, 50 new monitors for 10 years with a generous overhead comes to Rs 150 crore.
  2. Every kilogram of waste not picked up is likely to be burnt. The landfill capacity is at half of the waste generation rate. This activity is under the municipalities’ control to enforce and abolish, though there is an official ban on garbage burning.
  3. During the odd-even experiment, we estimated that Delhi needed at least 13,000 additional buses for full implementation of the shift. However, the final count stood at 2,000 buses contracted from schools and other private operators. The estimated average cost of a CNG bus is Rs 50 lakhs. If Rs 400 crore is up for spending, could this not manifest as 800 new buses in January 2017?
  4. All pavements should be improved to encourage walking and reduce dust on the roads. There are an innumerable number of ditches that are a result of other agencies’ works (such as telephone, cable, sewage and water pipes), and which are often left unfixed after the work is completed. If the city works to maintain roads and pavements, it will make a huge difference.

Air pollution in cities is largely a symptom of insufficient urban planning, whether due to waste burning, traffic or industrial emissions. The only way to address it is through looking at the principal sources and finding ways to reduce pollution at their level. It takes planning, inter-agency cooperation, good governance and political will, so proposing solutions that only mitigate it at a small scale (like traffic intersections) are not, and will not be, sustainable. They are ineffective at best, and waste valuable resources that take away from working towards a constructive solution. If the government is at all concerned about reducing air pollution, it needs to plan ahead, well in advance, and not find salves that appear to be proactive on the eve of the pollution (i.e. winter) season. We already know that every winter, starting around Diwali, Delhi implodes with rising pollution affecting most of its 20 million residents. Let’s be prepared for it next time by doing something that actually reduces it at the source.

Dr. Sarath Guttikunda is the director of Urban Emissions (India), an independent research group on air pollution, disseminating air quality forecasts for 640 districts in India.

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