The Pamba River (also called Pampa River) is the longest river in the Indian state of Kerala after Periyar and Bharathappuzha, and the longest river in the erstwhile former princely state of Travancore. Sabarimala temple dedicated to Lord Ayyappa is located on the banks of the river Pamba. The river is also known as 'Dakshina Bhageerathi'. During ancient times it was called 'River Baris' and jordan of malankara The River Pamba enriches the lands of Pathanamthitta District and the Kuttanad area of Alappuzha District and few areas of Kottayam Course The Pamba originates at Pulachimalai hill in the Peerumedu plateau in the Western Ghats at an altitude of . Starting from the Idukki district and traversing a distance of through Pathanamthitta and Alappuzha districts, the river joins the Arabian Sea through a number of channels. The basin extends over an area of with the entire catchment area within Kerala state. The basin is bounded on the east by Western Ghats and on the west by Arabian Sea. The river shares its northern boundary with the Manimala River basin, and the southern boundary with the Achankovil River basin. The river flows through Chittar, Vadasserikkara, Ranni, Ayroor, Cherukole, Keezhukara, Kozhencherry, Maramon, Aranmula, Arattupuzha, Edanad, Puthencavu, Chengannur, Kallissery, Pandanad, Parumala, Mannar, Kadapra, Melpadom, Thevery, Veeyapuram, Thakazhy, Pullangady, Pallathuruthy before emptying into the Vembanad Lake, while another branch flows directly via Karuvatta into Thottappally Spillway. One branch of Pamba called Varattar flows from Arattupuzha/Puthenkavu and along Edanad, Othera, Thiruvanvandoor, Eramallikkara and flows into Manimala River at Kallumkal East side. Another branch of Pamba flows from Kuthiathode and joins with Manimala River at Kallumkal West side, and branches out again at Nedumpuram from Manimala River and flows along Thalavady, Edathua, Champakulam, Pullangady, Nedumudy and empties into Vembanad Lake at Kainakary. This branch links with Mainstream Pamba River at Pullangady while continuing to flow to Vembanad lake. One branch of Achankovil River joins with Pamba at Paippad/Veeyapuram, while another branch flows into Pamba again via Karichal, Cheruthana. Perunthenaruvi is the major waterfall in Pamba river between vechoochira and Athikkayam Tributaries Azhuthayar Kakkiyar Kakkattar Kallar Aadhi Pamba Varattar Kuttemperoor Utharappalliyar Kolarayar Njunungar Madatharuvi Kozhithodu Thanungattilthodu Topography of the basin, reservoirs and command area Like all the river basins in Kerala, the Pamba basin also can be divided into three natural zones based on elevation, consisting of low land or seaboard, midland and high land. The coast for