Mumbai’s AQI worsens after three-day respite

Hazy visuals from Borivli West. Pic/Nimesh Dave

Following brief improvement in air quality, that is largely attributed to changing weather conditions and the BMC's implementation of Graded Response Action Plan (GRAP) 4 norms in areas where AQI surpassed 200 - pollution levels in Mumbai have once again deteriorated. After holding steady for three days, the air quality began to decline on Friday, only to worsen on Saturday. Monitoring stations at Borivili and Byculla, where construction work has been halted as part of dust mitigation efforts, shifted from moderate or satisfactory readings on Wednesday and Thursday to poor or very poor by the weekend.

BMC's GRAP 4 norms were imposed in areas where the AQI exceeded 200, specifically in Borivli East, Byculla, and Mumbai Central, halting all construction projects and mandating dust-mitigation measures. This decision followed air-quality data from December 28 and 29 showing AQI values above 270 in Navy Nagar, Colaba, Byculla, and Borivili East, indicating "poor" to "very poor" conditions. It was then that BMC commissioner Bhushan Gagrani, took strict measures to combat the deteriorating air, which he attributed to "climate change, vehicular emissions, and dust from construction sites."

On December 30 Gagrani ordered a shutdown of construction in Borivli East within 24 hours, stating that work would only resume once sites complied with The Dust Mitigation Guidelines. By December 31 itself, AQI levels immediately improved: Borivli East (IITM) dipped to 97, and Byculla recorded 131. Data from January 1 and 2 continued to show improved air quality, with Borivli East fluctuating between AQIs of 97 and 134, and several stations, including Navy Nagar - Colaba, slipping into the moderate and satisfactory range.

Meanwhile, the Maharashtra Pollution Control Board (MPCB) issued notices to both the BMC and MMRDA for violating guidelines, and served a separate notice to the Indian Institute of Tropical Meteorology (IITM) regarding the recalibration of its Colaba station.

The Figures don't lie

On January 4, Saturday afternoon (around 3 pm), Chembur's AQI stood at 238, while Ghatkopar was 306. Just two hours later, at 5 pm, the readings further worsened to 281 in Chembur and 318 in Ghatkopar. Borivli East-MPCB recorded an AQI of 304 (very poor), Byculla-BMC hit 263, Chembur-MPCB reached 281, and Ghatkopar-BMC rose to 318.