Air Quality in Kathmandu Valley Improves With Onset of Monsoon

The impact of rainfall and strong winds has lowered the Air Quality Index (AQI) in Kathmandu Valley to 47, which falls within the healthy category. A few weeks ago, Kathmandu was ranked the most polluted city globally, but it has now improved to 66th place. Knowledgeraj Subedi, Director General of the Department of Environment, has emphasized the need for long-term pollution control measures. (April 5, Kathmandu)

According to the latest AQI data as of 11 a.m. today, the air quality in the valley dropped to 47, categorized as ‘Good’. Previously, Kathmandu held the top spot among the world’s most polluted cities, but it has now dropped to 66th. The AQI classifications are: 0–50 ‘Good’, 51–100 ‘Moderate’, 101–150 ‘Unhealthy’, 151–200 ‘Unhealthy for Everyone’, 201–300 ‘Very Unhealthy’, and above 300 ‘Hazardous’.

On April 23, the AQI had surged to 247, placing Kathmandu in the ‘Very Unhealthy’ category, raising serious health concerns for the general population. Experts had warned at that time that the high pollution levels would exacerbate respiratory problems. According to Director General Subedi, prolonged dry spells cause accumulation of dust, smoke, and pollutants from forest fires in the atmosphere. “During dry weather, increasing forest fires release smoke that accumulates in the valley, significantly raising pollution levels,” he explained.

“Polluted air masses arriving from neighboring India also affect Kathmandu’s air quality,” he added. The recent heavy rainfall has helped wash away dust and smoke while increasing air circulation, leading to improved air quality. Subedi stressed that sustainable and environmentally friendly development strategies must be effectively implemented for long-term pollution control. Although the recent improvement provides some relief to valley residents, experts underscore the urgent need to focus on permanent pollution mitigation solutions.