The civic body set up 168 artificial ponds across the city, five times more than last year. (File)

THE NUMBER of idol immersions in Mumbai dipped by 32 per cent compared to last year, as Ganeshotsav ended on Tuesday. The civic body recorded 1.35 lakh immersions, out of which 70,233 idols were immersed in artificial lakes, a two-fold increase from last year. Last year, 1.96 lakh immersions were recorded, out of which 33,925 idols were immersed in artificial lakes. The civic body set up 168 artificial ponds across the city, five times more than last year. In addition, there were 37 mobile immersion sites.

Muted celebrations and no processions – due to the Covid-19 pandemic – also led to a dip in noise levels during Ganesha festival, according to NGO Awaaz Foundation, which advocates against noise pollution in the city.

The Brihanmumbai Municipal Corporation (BMC) had appealed to residents to avoid visiting the seashore for immersion. Civic officials said they wanted residents to use the nearest artificial pond for visarjan and take out small processions so as to ensure distancing.

The NGO found that noise levels touched 94.4 decibels (dB) when firecrackers were used near New Prabhadevi Marg on Tuesday. The highest noise level recorded during the 10-day festival was 100.7 dB from drums during a procession at Worli Dairy in South Mumbai, on August 23.

On Anant Chaturdashi, noise levels remained below 77 db, recorded at 11 locations between 8 pm and midnight. Girgaon Chowpatty, one of the main immersion sites, recorded noise levels at 75.4 db at midnight, which was noise from traffic, the report stated.

This year, noise levels on the last day of the festival were much lower as compared to data recorded since 2003, anti-noise campaigners stated in a report.

Last year, the highest noise level was recorded only on Anant Chaturdashi at 121.3 dB near Girgaon Chowpatty. The highest noise level over the past 17 years was recorded during Ganeshotsav 2015 at 123.7 dB, followed by 123.2 dB recorded in 2013.

The Brihanmumbai Sarvajanik Samanvay Samiti (BSGSS), the umbrella body of Ganesh mandals, said it directed all mandals in the city not to violate noise rules. Since 2015, police, accompanied by activists, have measured noise levels from loudspeakers at mandals. In line with the Bombay High Court’s orders, criminal cases are registered against mandals found violating noise rules, under the Environment Protection Act. Unlike previous years, police did not receive any noise-related complaint this year.

According to norms, noise levels in “silence zones” cannot exceed 50 dB during the day and 40 dB after 10 pm. In residential areas, levels are set at 55 dB during the day and 45 dB after 10 pm, while in commercial zones, the levels are capped at 65 dB during the day and 55 dB after 10 pm.