High Quality Content by WIKIPEDIA articles! Vamanapuram River is an 88-km long river in southern Kerala. The river originates in the Chemunjimotta hills (alt. 1860m) hills on the southern side of the Western Ghats, and flows through Thiruvananthapuram and Kollam districts of Kerala.It ends in AnjengoLake(Anchuthengu Lake) near Varkala. The two tributaries of this river are the Upper Chittar Manjaprayar streams.