Delhi’s AQI Gets Worse as October Begins With High Pollution

Delhi’s air quality continued to get worse on Sunday, marking the fifth straight day of rising pollution levels. The national capital also recorded one of its worst starts to October in recent years, based on data from the Central Pollution Control Board (CPCB).

The city recorded an average AQI of 187 at 4pm on Sunday. This falls in the “moderate” range and was Delhi’s highest AQI in 82 days.

Pollution levels had been rising since the end of September. Delhi recorded an AQI of 171 on Saturday, 174 on Friday and 166 on Thursday. The level had earlier been 129 before the recent rise began.

PM10 remains the main pollutant

PM10 was the main pollutant recorded in Delhi’s air. These particles are often linked to road dust, building work and farm fires.

The rise came after five days of “satisfactory” air quality. Rain and strong winds had helped clear pollutants from the city during that period. Once the rain stopped and winds became weaker, dust and other pollutants began to build up again.

Delhi’s AQI reached 197 at 9am on Sunday before falling a little later as wind speeds increased.

Mundka records the highest AQI

Pollution was high in several parts of Delhi. Of the 43 active monitoring stations, 14 recorded AQI levels in the “poor” range at 4pm.

Mundka recorded the highest AQI at 273. Mathura Road CRRI and Narela both recorded 257, while Jahangirpuri reported an AQI of 237.

Delhi Cantonment had the lowest AQI in the city at 97, which falls in the “satisfactory” range.

Jinitha Varghese, program manager at EnviroCatalysts, said rain in late September had helped lower pollution for a short period. After the rain stopped, warmer weather and weaker winds allowed dust and other pollutants to stay close to the ground.

She said Delhi needs lower pollution from several sources throughout the year. These sources range from power plants and factories to waste, heavy traffic, road dust and farm fires.

Pollution may rise further in the coming weeks

Delhi-NCR generally starts seeing higher pollution from around mid-September. Farm fires can add more smoke to the air as winter gets closer. Fireworks during the festive season, especially around Diwali, can also cause pollution levels to rise.

The Commission for Air Quality Management (CAQM) has said PM2.5 is a major pollutant during the winter months. Vehicle smoke, factory emissions, power plants and burning of plant waste can all add to the fine particles in the air.

Rain may bring some relief

Delhi recorded a minimum temperature of 24.1°C on Sunday, while the maximum temperature reached 36.4°C.

The India Meteorological Department (IMD) said the minimum temperature may fall to 21-23°C during the week. Monday is likely to remain clear, while partly cloudy weather may return from Tuesday. Very light rain is also possible on Tuesday.

Amateur meteorologist Navdeep Dahiya said mild western disturbances may affect the region from October 7. Another weather system may arrive after October 20 and could bring rain to parts of north India.

Rain could help lower pollution levels for a short time by washing some dust and particles out of the air.

CAQM finds road dust violations

The CAQM also found 17 violations linked to road dust and the build-up of construction and demolition waste during an inspection on Saturday.

Officials checked 25 stretches covering about 35 km of Delhi’s Inner and Outer Ring Road. The commission has asked the Public Works Department and other agencies to take action and fix the problems quickly.

With pollution already rising at the start of October, road dust, waste, traffic and other local sources remain key concerns for Delhi as the colder months approach.