Periyar and Pamba River Basin The Periyar River with a length of 228 km is the second longest river of this basin. It rises from the forest –clad Sivagiri peak, 80 km. south of Devikulam at an elevation of 2,438 m above sea level. The total drainage area of the river is 5,243 sq. km., out of which 113 sq. km. lies in Tamil Nadu. The Pamba is the third longest river of the basin. It is 177 Km. in length with the total drainage area spread of 1961 sq. km. It is formed by the confluence of the rivers Pamba Aar, Kakki Aar, Arudai Aar, Kakkad Aar and kali Aar. Area: Periyar and others Sub Basin consists an area of 21895.21 sq. km. Watershed: Periyar and others sub basin contains of 37 watersheds with size range of 341 – 934 sq. km. Population: 14162844 in 14 districts. Agro ecological zone: Hot humid perhumid ecoregion with red, lateritic and alluvium- derived soils. The other two zones are hot semi-arid eco-region with red loamy soils and the hot sub-humid to semi arid eco-region with coastal alluvium derived soils. Major irrigation projects: Pamba Irrigation Project: This project, located in Pattanamthitta district, aims at the utilization of the waters of Sabarigiri Hydro Electric project for irrigation purpose. The water is let into the river Kakkad, a tributary of Pamba River, and is picked up at Maniyar by a barrage. The water, thus collected is diverted through a canal on the left bank of the river. The project consists of a barrage of length 115.22 m with FRL at 34.62 m. The Pamba Project and its associated structures (Pamba Barrage) have a CCA of 21.13 Th ha and ultimate irrigation potential of 20.72 Th ha. Periyar Valley Irrigation Project: This project envisages the utilization of the tail race discharge from the completed Hydel scheme in the Muthirapuzha tributary of river Periyar together with the controlled release from Ennackal dam constructed by Kerala State Electricity Board under Hydel scheme across the Idamalayar tributary and the dependable run off from the uncontrolled catchment of Periyar river. The project aims for irrigating an area of 32.80 Th ha (CCA) of land lying on the left bank of Periyar river through a network of canal system and controlling devices. Inter-basin Transfer Links: The Pamba – Anchankovil – Vaippar Link: This link proposes to divert 634 Mcum of water from the surplus available in Pamba and Anchankovil basins of Kerala state to Vaippar basin for irrigating an area of 91,400 hectares in the drought prone districts of Tamil Nadu. The length of main canal is 50.68 km, and two tunnels of length 8 km and 9 km exist. Ecological significance: Silent Valley National Park, Periyar Tiger Reserve, Thattekad Bird Sanctuary are located in the basin. Issues Related to the river basin: Pollution: The lower reaches of the Periyar are heavily polluted. Industries in the Eloor industrial zone discharge waste into the river. Greenpeace India describes the lower Periyar as "a cesspool of toxins, which have alarming levels of deadly poisons like DDT, endosulfan, hexa and trivalent chromium, lead, cyanide, BHC”. Illegal sand mining: Illegal sand mining from the Periyar is another major environmental issue. Studies have pointed out that the quantity of sand being mined from the Periyar is at least 30 times the actual quantity that can be taken out without causing damage to the river’s environmental system (Source: The Hindu, October 6, 2013) Dispute: The control and safety of the Mullaperiyar dam on the river and the validity and fairness of the corresponding lease agreement have been points of dispute between Kerala and Tamil Nadu states .