A large idol of the elephant-headed Hindu god Ganesha sat in the back of an open truck travelling along a busy street in India’s financial capital, Mumbai, dwarfing other objects on the road.

Hundreds of devotees walked alongside, singing hymns glorifying the god of new beginnings, believed to be the remover of obstacles and granter of wishes.

The devotees took the idol to their small but densely populated neighbourhood, where they and others will worship it for 10 days. Many will whisper their wishes in Ganesha’s ear and present him offerings of his favourite sweet, called modak, a dumpling filled with coconut and jaggery.

At the end of the festival known as Ganesh Chaturthi, devotees will transport the idol to a nearby beach where they will ceremonially immerse it in the sea. Ganesha will thus return to his heavenly abode after being made aware of people’s wishes.

During the festival, which started on September 7, millions of devotees across India celebrate the birth of Ganesha, by immersing idols of him, big and small, in ponds, rivers and the sea.

Ganesh Chaturthi is also widely celebrated by the sprawling Indian diaspora all over the world.

But the festival finds its most fervent followers in Mumbai, a major coastal metropolis in western India.

Hundreds of migrant artisans arrive in the city each year to help meet the seasonal demand for the idols. Travelling a significant distance by train from the north, usually without their families, these male artisans spend about four months sleeping, eating and building statues at various workshops in the city.

The preferred building material is quick-setting gypsum plaster, commonly known as plaster of Paris. With it, the builders can construct large, relatively light idols in a short time.

While the environmental impact of immersing large numbers of plaster statues in bodies of water is a subject of debate, demand for idols made of mud has increased. Vishal Shinde, a manufacturer of idols in Mumbai, has made 470 mud idols this year.

“We are receiving more orders each year to build mud idols painted with watercolours as people are becoming more concerned about the environment,” Shinde said.