The National perspective plan envisions about 150-million-acre feet (MAF) (185 billion cubic meters) of water storage along with building inter-links.  These storages and the interlinks will add nearly 170 million acre feet of water for beneficial uses in India, enabling irrigation over an additional area of 35 million hectares, generation of 40,000 MW capacity hydro power, flood control and other benefits.
The total surface water available to India is nearly 1440-million-acre feet (1776 billion cubic meters) of which only 220-million-acre feet was being used in the year 1979. The rest is neither utilized nor managed, and it causes disastrous floods year after year. Up to 1979, India had built over 600 storage dams with an aggregate capacity of 171 billion cubic meters. These small storages hardly enable a seventh of the water available in the country to be utilized beneficially to its fullest potential. From India-wide perspective, at least 946 billion cubic meters of water flow annually could be utilized in India, power generation capacity added and perennial inland navigation could be provided. Also some benefits of flood control would be achieved. The project claims that the development of the rivers of the sub-continent, each state of India, as well as its international neighbours stand to gain by way of additional irrigation, hydro power generation, navigation and flood control. The project may also contribute to food security to the anticipated population peak of India.
The Ganga-Brahmaputra-Meghna is a major international drainage basin which carries more than 1,000 million acre feet out of total 1440 million acre feet in India. Water is a scarce commodity and several basins such as Cauvery, Yamuna, Sutlej, Ravi and other smaller inter-State/intra-State rivers are short of water. 99 districts of the country are classified as drought prone, an area of about 40 million hectare is prone to recurring floods. The inter-link project is expected to help reduce the scale of this suffering and associated losses.
The National Perspective Plan comprised, starting 1980s, of two main components:
#Himalayan Rivers Development, and
#Peninsular Rivers Development
An intrastate component was added in 2005.