A project aimed at surveying the Mahaweli River and the dry zones of the Northern and Central provinces had been commissioned by Mrs Bandaranaike’s Government in 1961. The plan of operation signed on 12 October 1964 between Ceylon, the United Nations Special Fund and the Food and Agriculture Organisation (FAO) saw the commencement of work on 27 October 1964 to evolve a Master Plan for full development of the water resources for irrigation and hydropower.