King kavera performed tapasya because he wished to help people. Pleased with him, Shiva appeared and blessed him with a daughter who would fulfil his wish.
He named her Kaveri and married her to Sage Agastya. A demon, named Shoorapadma, wanted to trouble people so he prevented rain from reaching the earth.
Kaveri prayed to the gods to help the people. One day, Sage Agastya went to a lake for a bath. Since he could not leave Kaveri alone in the ashram, he turned her into water and put her in his kamandala,
Kaveri transformed in to a river utensil for carrying holy water. As he entered the lake, he left the kamandala on the bank. Meanwhile, Ganesha took the form of a crow and overturned the kamadala.
The water was released and Kaveri became a river. She helped the suffering people by providing them with water.