Rivers of South India are dependent on the monsoons and shrink during the dry season.The line created by the Narmada River and Mahanadi river is the traditional boundary between northern and southern India. The Narmada flows westwards in the depression between the Vindhya and Satpura ranges. The plateau is watered by the east flowing Godavari and Krishna rivers. The other major rivers of the Deccan plateau are the Pennar and the Tungabhadra, a major tributary of the Krishna.