Rains brings temporary respite from poor air quality in Guwahati
GUWAHATI: With the change in season, Guwahati is witnessing an improved air quality over the past three months. This was revealed by data from the Pollution Control Board of Assam (PCBA) on air quality in Guwahati.
As per the data, the air quality index (AQI) as recorded in six different monitoring stations in March this year was 144. Further, the quality of air improved and the AQI became 104 in April and this further became better as the AQI recorded in May was 62.
The AQI is based on data recorded from six different air quality monitoring stations at various places in Guwahati.
The air quality index is used to measure the pollution levels in air and is an indicator of how clean or polluted the air is. It also indicates the health effects of breathing polluted air.
An AQI of 51-100 is considered ‘satisfactory’ and is linked to minor breathing discomfort to sensitive people. Further, AQI between 101 and 200 is considered ‘moderate’ and is associated with breathing discomfort to people with lung disease, heart disease, children and older adults.
Further, the PCBA data showed that PM 10 levels have also become better in Guwahati over the past three months. PM 10 is an air pollutant which is particulate matter measuring 10 micrometers or less in diameter.
While PM 10 level was 165 in March, it declined to 106 in April and further went down to 62 in May.
Currently there are six air quality monitoring stations in Guwahati and 23 stations all over the state which help in measuring different parameters of air quality.
Further, the air quality is usually at its worst around Diwali festival in the months of October and November, say experts.
Earlier, the PCBA data showed that during November 2018, the pollutants in the air- both PM 2.5 as well as PM 10 were recorded to be much higher than the prescribed level.
As per the Central Pollution Control Board (CPCB), the prescribed safe limit for PM 2.5 is 60 micrograms per cubic metre and for PM 10 it is 100 micrograms per cubic. However, the average PM 2.5 level as recorded for November was 97.9 while the average PM 10 level was 162.2.
Meteorological changes behind better air quality: Experts
Gokul Bhuyan, senior environmental engineer at PCBA told G Plus that meteorological conditions are the reason behind the recently improved air quality.
“During the dry season when there is no rain, the suspended particulate matter (often hazardous in nature) in the air remain high. However, when it rains, all particulate matter precipitate along with the rain.”
Bhuyan added that the air quality is set to improve further as the monsoon period progresses. The pollutants in the air are the highest in the dry season and start increasing from September onwards when the rains stop, he said.
Additionally, Guwahati was selected as part of 102 non-attainment cities by the Central Pollution Control Board (CPCB).
The ministry of environment had released a draft of the National Clean Air Programme (NCAP) in April 2018. In the draft, Guwahati had featured among the ‘non-attainment cities’ along with Nagaon, Nalbari, Sibsagar and Silchar from Assam. A total of 94 cities had earlier been identified as non-attainment cities.
Non-attainment cities are those in which the prescribed Ambient Air Quality Standards as set by the CPCB are violated.
The NCAP is a national programme to tackle the increasing air pollution across the country. It suggests several measures to reduce air pollution levels in a collaborative approach.
Accordingly, Guwahati was mandated to make the air action plan to better its air quality.
Proposed air action plan to tackle air pollution submitted
Talking about the steps taken by the state pollution control board to improve air quality, authorities said that the board has formulated a combined action plan which will be implemented together by the Public Works Department (PWD), Guwahati Municipal Corporation (GMC), PCBA and the transport department. The plan has been submitted to the CPCB, said officials.
“PWD will ensure black topping of all roads, so that road dust does do not float and pollute the environment,” informed a PCBA official.
Similarly, the transport department will be involved for controlling and managing traffic and vehicles in the city while the GMC will spray water on the roads to reduce dust particles. The transport department will also keep a check on pollution levels of vehicles, which is another major cause of air pollution in the city.
Authorities informed that the comprehensive action plan has been prepared in consultation with all the concerned departments.
“The combined action plan was prepared last month. It was submitted a few months earlier too but the CPCB didn't approve of it since it didn't comprise allocation of budgetary provision,” said a source.
Apart from this, officials informed that mass awareness programmes will also be implemented in the city by the PCBA in collaboration with the transport department.