The city civic body is planning to offer Durga puja organisers the option of melting the idols with jets of Ganga water instead of consigning them to the river, drawing inspiration from an environment-friendly immersion process followed by Naihati Kali pujas.

In the proposed process, the melting of idols, after completion of the religious rituals, symbolises immersion.

“We want to introduce the wash-melt process, at least at Babughat, after Durga Puja. Discussions are on with the fire services. The puja organisers will have the option of choosing this process or going for the conventional one,” said Debasish Kumar, mayoral council member (parks and garden).

He revealed the plan during a recent meeting of the state pollution control board to discuss green norms to be followed during Puja. Senior officials, environmentalists and representatives of puja organisers attended the meeting.

Kumar claimed there was no religious bar on wash-melt “immersion”. As one of the main organisers of the Tridhara Sammilani puja, a CESC The Telegraph True Spirit Puja winner in 2009, he offered to immerse its idols in this manner.

Representatives of many of the clubs welcomed the proposal. “The Hooghly is extremely polluted and immersing thousands of idols in it is only adding to the pollution. The wash-melt model is much better,” said Nitish Saha, the president of Forum for Puja, the consortium of more than 100 pujas in the city.

“The actual immersion happens long before the idol is consigned to the river. Hence, the idol can definitely be melted with Ganga water. However, it may take some time to change the mindset of the people,” said Partha Ghosh of the Sibmandir puja committee and vice-president of the forum.

In Naihati, Kali idols are melted mostly out of compulsion. The huge idols — some more than 40ft high — cannot be ferried to the Hooghly since the railway lines across many of the access roads are not high enough.

“We have been immersing idols this way for more than five years. There is no religious stricture against this process. People from the area actually gather and enjoy the melting of the idol, which takes about an hour and a half,” said a representative of a club in Naihati.

“This is a welcome move to minimise Ganga pollution. Despite the widespread use of lead-free paint last year, lead contamination of the river has increased,” said Krishnajyoti Goswami, a scientist working on lead pollution.