In  2019, the Delhi-National Capital Region saw a considerable improvement in air quality. Compared to the last four years, Delhi witnessed almost 50 per cent increase in the number of cleaner days annually, according to a report by the Centre for Science and Environment (CSE).

The development comes as a sigh of relief for the city as its Air quality index (AQI) mostly stayed in 'satisfactory' and 'moderate' zones in the bygone year. As per the index, the PM 2.5 levels in Delhi were under 'satisfactory' and 'moderate' categories for 120 days in 2019. There were only 68 such days in 2016. The pollution level under the 'very poor' category in 2019 lasted for only 72 days, while it extended for 125 days in 2016.  

The cleaner days in 2019, however, were majorly clustered in the summer and monsoon seasons only. The air quality breached severe levels in winters. Continued stubble burning in Punjab and Haryana added to the smog levels in November 2019, a significant rise from 2018. Although stubble burning contributed up to 30 per cent in Delhi's air pollution, vehicular pollution, domestic pollution, industrial emission, road dust, garbage burning and construction of infrastructure were other key contributors in the mayhem.

In such a scenario, the recent CSE report by Anumita Roychowdhury and Avikal Somvanshi, comes as a breath of fresh air for residents of the 'most polluted city on Earth'.

Here's how Delhi experienced cleaner days in 2019:

Between 1998 and 2003, a series of Supreme Court directives led to the eviction of big, polluting industrial units outside Delhi. Besides, replacement of diesel-run public transport with CNG buses, taxis, and autos; phase-out of old commercial vehicles and improvement in emission standards for vehicles were some of the first generation actions taken to curb pollution in the national capital. Initially, all these helped in stabilising the air, but some of these gains were subsequently undermined as the action slowed down and pollution kept increasing.

However, the momentum to take the air pollution problem revived seriously 2015 onwards. During this phase, several multi-sectoral and diverse actions were initiated. Between 2017 and 2018, the SC directed the government to notify a Graded Response Action Plan (GRAP) for emergency intervention during smog episodes. The court also directed a Comprehensive Action Plan (CAP) for sustained short and long-term actions across sectors in Delhi-NCR.

During this period, all coal-based power plants in Delhi were shut down. Ban on dirty fuels, including pet coke, furnace oil, and coal was notified to the industry and power sector officials. Further, measures were taken to ensure a substantial number of industrial units replace coal and other dirty fuels with natural gas. Small-scale industrial recycling units in places like Mundka saw a significant reduction in the burning of plastic waste.

In the transport sector, massive court interventions were made to control emissions from heavy vehicles. For instance, eastern and western expressways were built to divert truck traffic. An Environment Compensation Charge (ECC) was imposed on every truck entering Delhi and the entry of 10-year or older and overloaded trucks was banned. Through these initiatives, heavy vehicles entering Delhi through its 13 key points reduced to 2,000 in 2019 from 15,000 in 2015.

In 2018, BS-VI (Bharat Stage VI) fuel norms were introduced to further control pollution. The phasing out of 10-year-old diesel vehicles and 15-year-old petrol vehicles, and environmental pollution charges on big diesel cars and SUVs were also introduced.

The CNG programme also added to the cause. A blend of hydrogen and CNG was piloted as fuel for buses during this period. Now, it has been further scaled up for nearly the entire commercial vehicle fleet of the city. Pollution charge based on the 'polluter pays principle' was enforced in yet another effort to control pollution.  

TARGETS TO ENSURE CLEANER DAYS AHEAD:

While these measures saw a significant increase in the number of 'clean air' days in Delhi NCR, the capital has a long way to go in order to ensure a pollution-free city for its residents.

Avikal Somvanshi said, "The key problem is the government's Comprehensive Action Plan (CAP), that focuses on strict parking policy and on upgradation of the public transport system. Unfortunately, the plan has not been implemented fully." However, the development of Delhi Metro rail services, BS-VI emission norms, introduction of CNG technology in vehicles had largely given decent results in the battle against air pollution, Somvanshi added.

Somvanshi told BuisnessToday.In about the stark contrast in pollution level during Delhi's summers and winters. He stated, "The AQI was under 'moderate' category for 68 days in 2016, which increased to 120 such days in 2019 but all these days were during the monsoon and the summer.  Winter pollution remains equally bad as it was in 2016. So, winters have not become cleaner." He added, "We need to figure out which model has contributed the most in cleaning Delhi's air in order to reduce pollution even during the winters."

Bharati Chaturvedi, Director of Chintan Foundation stated a few clean days were not good enough for public health, because the slightest exposure to polluted air could result in severe consequences. Chaturvedi praised North Delhi Municipal Corporation (NDMC) for making Ajmal Khan road in Karol Bagh a non-motorised zone. Chaturvedi also suggested replicating the Ajmal Khan road model in other parts of Delhi.

"In terms of traffic decongestion, the Ajmal Khan road in north Delhi has significantly improved the quality of air in that area. We need to learn from the NDMC. Ajmal Khan model must be replicated and scaled up in more places in the city." She also said Delhi should introduce a congestion tax like London.

On Delhi's air pollution in winters and stubble burning, Chaturvedi said, "Pollution is not a winter problem, it is a chronic year-around problem. The burning of paddy will not make AQI 900. It will be bad for a few days but it won't go to that level. Stubble burning affects us because our air is already serious."

Chaturvedi also advised the government to discontinue sports events in the national capital. "Delhi government should completely stop promoting sponsored sports. We don't want cricket matches or sports marathons in Delhi."

Chaturvedi added that risk to life was higher while running in polluted air. Recently, Delhi had also lost the right to conduct the Under-17 Women's Football World Cup due to its poor air quality.