To be greeted by a traditional kolam, or rangoli, at the entrance of a building or household is hardly unusual in Tamil Nadu. The intricate pattern of rice flour is an ancient art that is believed to bring general prosperity into one’s home.

However, since February 3, visitors to the Lalit Kala Academy in Chennai have been greeted by a large, unusual kolam. Instead of the usual strokes of white powder, this is a kolam made of waste collected from the banks of Chennai’s Adyar river. Tucked into the grooves of the design are toothbrushes and rubber slippers, medicine containers, liquor bottles and plastic toys, including the popular cartoon character Chhota Bheem with his slingshot. This is Chennai-based artist Parvathi Nayar’s way of rethinking the city’s relationship with its polluted rivers.