Assam: Guwahati air quality worsens; experts question accuracy of govt AQI data
Guwahati: Growing alarm over Assam Guwahati’s worsening air quality has sparked fresh debate on whether official pollution figures mirror the city’s real situation.
Residents and experts increasingly suspect that the limited number of monitoring stations prevents the government from presenting an accurate assessment.
The Central Pollution Control Board (CPCB) reported Guwahati’s average Air Quality Index (AQI) at 109 on Wednesday, placing it in the ‘moderate’ category.
However, this average was calculated from only three out of the city’s four Continuous Ambient Air Quality Monitoring System (CAAQMS) stations. Guwahati’s monitoring network includes stations at the Pollution Control Board Assam (PCBA) headquarters in Bamunimaidam, Panbazar (Cotton University), the Gopinath Bordoloi International Airport, and IIT Guwahati. For the past two days, CPCB has published AQI readings that exclude one of these stations.
Independent platforms paint a grimmer picture. AQI.in recorded the city’s AQI touching 178 around midnight and again near noon on Wednesday. The November average stood at 119, which falls under the ‘poor’ category. So far in December, the city has averaged an AQI of 167—considered ‘unhealthy’.
Global air quality tracker IQAir also placed Guwahati’s AQI at 133 at 4.30 pm on Wednesday, a level classified as ‘unhealthy for sensitive groups’.
IQAir’s report considered data from CPCB stations at IIT Guwahati, Panbazar, and LGBI Airport, though the Bamunimaidam readings were unavailable.
The agency further warned that PM2.5 levels in the evening were nearly 9.7 times higher than the World Health Organization’s annual guideline.
Environmental experts insist that Guwahati urgently needs additional monitoring stations, especially in areas experiencing heavy pollution.
They argue that the AQI released by government agencies fails to reflect air quality around major construction zones, particularly near ongoing flyover projects.
Even as per official norms, the city should have at least five CAAQMS stations—two in residential areas, one in a traffic-heavy zone, one in a commercial area, and one in an industrial zone—along with manual monitoring sites.
IIT Guwahati’s Civil Engineering professor Sharad Gokhale echoed the need for expanded monitoring. He pointed out that several traffic chokepoints, including the increasingly congested Jalukbari junction, should have dedicated air quality stations.
He noted that the IIT Guwahati station, installed under the National Clean Air Programme (NCAP), monitors surrounding rural areas and nearby industrial units.
A recent satellite-based assessment of PM2.5 levels conducted by the Centre for Research on Energy and Clean Air (CREA) underscores the severity of the crisis.
The study revealed that 11 districts in Assam ranked among the country’s 50 most polluted districts in 2024, and all 34 assessed districts in the state exceeded the National Ambient Air Quality Standards (NAAQS).