The Supreme Court of India, in 2002 directed the central government to link major Indian rivers within 10 years. In December 2002, the government appointed a task force on interlinking of 37 rivers and the dead line was extended by 2016. The RIL project not only raises national issue but also give way to international conflict in South Asia over sharing of river waters. The paper examines the impact of the RIL project on the paradigms and working of Indian federalism. It is based on triangulation of theory and qualitative method that applies content analysis of primary and secondary sources to draw conclusion. It finds that in the Indian Constitution water is in the State List while inter-state river is in the Union List and taking up such a mega RIL project without the consent of the concerned states is unacceptable. It considers the directive of the Supreme Court indeed, as an act of judicial activism.