Ganapathi Bappa Moriya! It's the time when these chants fill the air, as Ganesha is paraded around the city and finally immersed in a water body. Ganesh Chaturthi or Vinayaka Chaturthi is one of the more popular festivals celebrated across the country.

The reason for its popularity is not just the universal appeal of the deity, but the celebrations that go with it too!

As is tradition, people bring home the idol of Ganesha, either a day before or on the day of Chaturthi. The idol is then decorated and worshipped for one, five, seven or 10 days depending on one’s practices and patience.
..
Celebrating nature

Traditionally, Ganesha idols were made of clay. Over the years, clay has been replaced by plaster of Paris and artificial colours have been used to make the idol attractive. However, the artificial colour and the plaster of Paris, turn our water bodies toxic and when immersed aquatic life is affected.

http://www.thehindu.com/features/kids/ecofriendly-ganeshas/article5109929.ece