The river is closely associated with the Chithirai festival of Meenakshi Sundareswarar temple at Madurai. On Chitra Pournami day Lord Kallazhagar (Vishnu), the elder brother of Goddess Meenakshi enters the Vaigai River. Legend has it that the festival is held to re-enact a puranic episode in which Lord Azhagar comes to the riverbank from his abode at Azagarmalai (30 kms from Madurai) to grant moksha to ‘Mandooka’ Rishi who was a great devotee of Vishnu, but was cursed earlier to turn into a frog.
According to another legend, Kallazhagar arrived late for the marriage of his sister Meenakshi with Lord Sundareshwara. Taking note that the marriage has already taken place, he plunges into the river Vaigai and walks through to nearby Vandiyur. Adults and children join together in spraying water at Lord Kallazhagar as he walks towards the river bank of Vaigai in total disappointment.