The main purposes of carrying out the program were the generation of hydroelectric power, controlling flood, making irrigation facilities for dry zone cultivation, settlement of landless and unemployed families by constructing and developing the physical and social infrastructure required for human habitation by using the waters of the Mahaweli River.
The Master Plan of Mahaweli Development Programme was prepared with the assistance of UNDP and FAO and recommended for stepwise implementation over a period of 30 years.
[3] The first phase of the program consisted of diversion headworks at Polgolla and Bowatenna, 40 MW hydropower plant at Ukuwela and an improved water supply to about 52,700 ha of existing irrigated land.
However, the newly appointed J. R. Jayewardene government in 1977 decided to speed up the program and complete it within its term of office of 6 years.
Which was consist of 12 projects and mainly confined to four head works in the initial works of the program, including the construction of Kotmale, Victoria, Maduru Oya, Randenigala dams and the downstream development of about 60,000 ha in Systems B and C and the Minipe anicut, the Right Bank Trans basin Canal and the Ulhitiya and Ratkinda reservoirs.