Kerala on Tuesday argued before the Supreme Court that the Mullaperiyar water agreement has become legally unsustainable after the state legislature passed the Kerala Irrigation and Water Conservation Act, 2003. The agreement was signed as a lease deed executed between the Government of the Maharaja of Travancore and Secretary of State for India on October 29, 1886. Senior counsel Harish Salve, appearing for Kerala, before the five-member constitution bench argued that Section 30 of the 2003 Act had explicitly taken away the rights of Tamil Nadu. On the opening day of Kerala’s argument, the counsel argued that this parent Act was not considered by the Supreme Court when it passed the order to sanction raising of water level in the dam up to 142 feet in 2006. The judgment is therefore “per incuriam”, Salve argued. The counsel, however, conceded there were failures on Kerala’s part in bringing to SC’s notice the full implications of the 2003 Act. ‘Periyar an intra-state river’ Kerala assembly had passed a Bill in 2006 itself to limit the water level in the dam to 136 feet. Defending this decision of Kerala, Salve argued that all rights, except the Constitutional rights, can be regulated by the legislature. “Safety of the dam is a matter of regulation. In my state, I will regulate heights of dams in my territory’’, the counsel argued. He said there was no usurpation of judicial power by amendment act 2006 as argued by Tamil Nadu, as the legal right to that state had already been taken away by 2003 Act. Kerala’s counsel strongly contested the claims that Periyar is an inter-state river. Periyar is an intra- state river since no part of it flows through Tamil Nadu; it originates in Kerala, flows entirely through Kerala and joins the Arabian Sea in the state. This has been admitted by Tamil Nadu. Just because 2% of Periyar’s catchment area falls under Tamil Nadu, that state cannot claim any interstate right on the river. Only a valley falls under Tamil Nadu, and the Constitution gives explicit differentiation between river and valley, the counsel argued.