Which of the following river acts as a divider between Assam and West Bengal?

The correct answer is Sankosh. Key Points The Sankosh is one of the major north-bank tributaries of the Brahmaputra river . Sankosh river forms the boundary between Assam and West Bengal . It originates from the snow-clad greater Himalayan ranges of Tibet. In Bhutan, the river is known as Mo-chu and in the plain of Assam beyond Srirampur is known as Gangadhar . It crosses a distance of 214 km in Bhutan and 107 km in India. The river Sankosh is formed by the confluence of two major tributaries. The Pochu from the east and Panakh or Mo-chu on the west. Several other tributaries originating from the Himalayan ranges join the Sankosh river to form the main river system. The Sankosh generally flows in narrow gorges, steep gradients up to the Indo-Bhutan border, and then flows with a flatter slope. The lower reach of the river downward to Srirampur is subjected to flooding annually. The river traverses a length of 321 km from source to outfall and the catchment area is 10,345 sq. km. Its average width is 207 M.