Guwahati, June 24 -- The Ranganadi River, a sub-tributary of the Brahmaputra, originates in the Himalayan foothills of Arunachal Pradesh at an elevation of approximately 3,400 meters. Spanning a total length of 150 km, it flows for about 90 km through the hilly terrain of Arunachal Pradesh before entering the plains of Assam, where it continues for another 60 km. The river's catchment area covers roughly 2,941 square kilometers, with 31 percent lying within Assam. It enters Assam at Johing in Lakhimpur district and eventually merges with the Subansiri River at Pokoniaghat. The river's average annual discharge is estimated at 3.78 BCM (billion cubic meters), translating to a flow rate of around 120 cumec (cubic meters per second).

By natu...