The Mahanadi is known as an Orissa river but in which state does it originate?

The Mahanadi River originates in the Dhamtari district of Chhattisgarh (formerly part of Madhya Pradesh before Chhattisgarh became a separate state in 2000). While it is primarily associated with Odisha (Orissa) where it forms a major delta, its source lies in the northern highlands of the Eastern Ghats in what was historically Madhya Pradesh.