Section 4(2) in The Inter-State Water Disputes (Amendment) Act, 2002
(2)The Tribunal shall investigate the matters referred to it and forward to the Central Government a report setting out the facts as found by it and giving its decision on the matters referred to it within a period of three years:Provided that if the decision cannot be given for unavoidable reasons, within a period of three years, the Central Government may extend the period for a further period not exceeding two years.
