Kathmandu Valley Recent Pollution levels, Causes, And Effects

  • blog
  • 31st Mar, 2021

Kathmandu, known as the city of temples is now the city of pollution. It is the central hub for indoor and outdoor tourists and millions of people from all around the country. Pollution has always been a problem in cities because of all the vehicles, factories, and other causes. Recently the condition has worsened because of the additional drought and 479 wildfires all around Nepal.

Since Friday afternoon the city with the worst air quality index all over the world. An Air Quality Index reaching as high as 500 μg/m³. According to the US Embassy measuring station at PhoraDarbar, the Air Quality Index (AQI) remained above 500 from 10 PM till 4 AM. It has fallen to 480 but still, the city is covered with haze and smoke all around. The air quality index is calculated by measuring Particulate matter (PM 2.5). PM 2.5 are tiny particles or droplets in the air that are two and one-half microns or less in width.

The high concentration of PM 2.5 particles in the air due to pollution, wildfire, and other factors. They created a layer of haze all around the city affecting the flights. Generally, AQI level under 100 μg/m³ is considered moderate. But it has exceeded 400 μg/m³ which comes in the category of very unhealthy and hazardous. Therefore the government has decided to close educational institutions from Tuesday for 4 days hoping the situation to get better. If the situation does not get better or if it worsens then the government has planned to extend it. Along with educational institutions, flights have been affected as well.

Recent pollution levels in Kathmandu

From the data collected from the previous years, it is hard to say whether the situation is going to worsen. Things are going to get better soon. In the year 2017 45.9 μg/m³ was the highest PM2.5 reading of Kathmandu and it increased to 54.4 μg/m³. Moving onto 2019, the pollution decreased as it again came down to 48 μg/m³. The air quality index had been going down and pollution was decreasing. In the year 2020 because of the lockdown and shutdown of many industries. Now in 2021, the economy has started growing and on top of that, more vehicles are running. To make the situation worse there were 479 wildfires in the area near Kathmandu, the all-time highest in Nepal. All these have led to the highest PM2.5 concentration ever at 411 at 9:45 am on Saturday, 27th March 2021.


During the lockdown for almost a year, there were many businesses and works paused. After the lockdown ended all the works have started taking a pace in return causing a lot of pollution. The economy is growing and so is the air pollution. In addition to that, there hasn’t been big rainfall. Only a few scant rainfalls have been recorded since the month of December which aided in many wildfires. The country received only 25% of normal rainfall in this season. According to Sundar Prasad Sharma, an under-secretary at the Department of Soil Conservation. There was the highest record of 479 wildfires all around Nepal on Thursday. The area near Kathmandu valley also caused the air quality and pollution in Kathmandu to increase.

The drought, pollution, and wildfire collectively have led Kathmandu to become the city with the worst Air Quality Index. Besides all these factors the topology of the land structure of Kathmandu valley being a bowl-shaped basin is not allowing the air to flow out. The slow wind speed and the shape of Kathmandu valley have trapped pollutants in the air during this time.

Effects of the high Air Quality Index

The AQI being as high as 411 μg/m³ is considered very unhealthy and hazardous. Which has led the government to decide on closing the educational institutions all around the country from Tuesday until Friday. The high level of PM 2.5 particles in the air could cause skin and eye allergies. Since the PM 2.5 particles are very fine which are two and one-half microns or less in width. They can easily get into our respiratory tract and the lungs and cause health issues. During the sensitive time of Covid-19, this can create further complications so it is a must to wear a mask. It is better to stay inside than going out at such times. Physician Khem Raj Bhusal has warned that a high concentration of PM 2.5 particles could cause skin and eye allergies too.

Besides the health effects on individuals, even the flights have been affected by the pollution. The smoke and haze covered in Kathmandu compelled Tribhuvan International Airport to close from 2:10 PM on Friday. Since the visibility is just at 1000 meters, they can’t operate flights which has left many passengers stranded and inconvenienced.

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