For this event, a girl will be coming out of the Ganga river i.e. holy water by dressing up in form of Goddess Ganga. It will be a replica of the scene of Goddess Ganga going from the Swarg to Earth and from the sky shower of flowers will be occurred. The Goddess Ganga came on Earth as it was becoming over land. The main purpose of reflecting on this event will be to spread the importance of Goddess Ganga to mankind.
In ancient times, there was a time when the earth was ruled by demons, and thus, these demons used to annoy the sages who were meditating. The same scenario continued for a longer time but, one day, all the sages prayed to the sage Agastya for freeing them from such torture by the demons, as the result, sage Agastya drank the sea along with the demons. Although the demons came to an end, the earth became void of water and the humans were facing the problems. Hence, the humans prayed to another sage named Bhagirath for freeing them from this calamity of droughts.
For making the humans relieved from this scenario, he prayed for thousands of years and then, went to Brahma for praying to him that he take down the river Ganga to earth.