Kathmandu, the capital city of Nepal, has a population of around 3.5 million. Rapid and haphazard urbanisation in the last few decades has resulted in the degradation of the environment, predominantly in terms of air pollution.
The ‘polluter pays' principle was introduced in 1972 in order to address this issue. It urges the polluters to pay for the damage done to the natural environment. But air pollution issues are continue to increase.
In terms of air pollution, the 2016 Environmental Performance Index (EPI) ranked Nepal 177th out of 180 countries. Moreover, Kathmandu is ranked as one of the most polluted cities in Asia: according to the airvisual.com, Kathmandu is the seventh most polluted city.
The high mountains around the Kathmandu valley allows air pollution to accumulate in the city.
The number of vehicles in the valley during the last two decades has increased ninefold, and reached 922,900 in total during 2015, according to the Department of Transport Management in Nepal.
Motorcycles and passenger vehicles such as jeeps, cars and vans accounted for 92 percent of total registered vehicles in Bagmati by the end of 2014-15. All of these vehicles degrade the air quality by emitting huge quantities of smoke into the ambient environment.
There is a proportionately very high consumption of gasoline and diesel in the valley. Kathmandu valley requires half of the total gasoline consumed in Nepal. Similarly, one-fifth of the total diesel is used in Kathmandu.
Besides the quantity of fuel consumption, the poor road condition of older vehicles is triggering air quality problems in the valley.
In addition, vehicles passing over broken or traveled road release huge amounts of dust particles into the air, worsening air pollution further.
The size of dust particles are larger compared to biomass burning or vehicular emissions. This can significantly affect the local environment and the health of people living nearby.
Krishna Kumar, a local business person at Kirtipur explained: “Many businesses have gone down due to high amount of road dust. When a vehicle passes by, dust is released into the air and pollutes the clothes that are kept for selling and the customers do not like the polluted ones”.
Similarly, the hotel business (khaja ghar) of Ram Karki has also slowed down majorly due to road dust emission.
These two are just representative examples of millions of people who are directly or indirectly affected by dust, a burning issue of the twenty first century.
The effect of dust is not limited to human beings, but is also felt by plants, particularly to those closer to the road. The leaves of plants are covered in dust particles which limits the photosynthesis rate and affects the plants growth and natural beauty.
Vehicular emissions or traffic related particulate matter has serious health effects such as increased respiratory disease, reduced lung function, asthma, cardiac arrhythmias, heart disease etc. The World Health Organization (WHO) reports fine particulate matter of up to 140 µg m-3 - which is around ten times higher than the WHO limit.
Globally, air pollution results in around seven million deaths annually. In Nepal and Kathmandu the annual premature death due to air pollution hit 37,399 and 9943 respectively, according to a Republica news report published on 23 November 2019. This indicates, around a quarter of the total deaths due to air pollution in Nepal are in Kathmandu.
The victims of air pollution urgently require an appropriate action plan for mitigating these problems.
Hemraj Bhattarai is a graduate student from University of Chinese Academy of Sciences, Beijing, China, and is currently working on air pollution issues at Kathmandu Center for Research and Education, Nepal.