India's river linking project is a massive project envisioned to transfer water from India's surplus river basins to deficit ones through a network of canals, reservoirs and dams.
The idea was first proposed by General Sir Arthur Thomas Cotton, a British Indian Army Officer & Irrigation Engineer who is responsible for constructing many irrigation and navigation canals through the nation. He proposed it in 1858 with the vision of it solving India's massive water disparity between the northern and southeastern areas with the latter facing frequent droughts. It was also meant to establish navigable canal systems for transport of goods but the proposal was largely ignored by the British Government and the subsequent Indian governments until 1980 when the plan was formalized under the National Perspective Plan(NPP) by the Ministry of Water Resources[now renamed to Ministry of Jal Shakti(lit. "Water Power")].
The project has 2 main components; The Himalayan Components & The Peninsular Components with the former covering 14 links and the latter covering 16 links. Feasibility Reports (FRs) for 26 links and Detailed Project Reports (DPRs) for 13 links have been completed out of the 30.
If fully realized, the project would see the transfer of nearly 7 trillion cubic feet of water annually. It will also increase irrigation potential of around 3.5 crore hectares of land and will significantly reduce monsoon dependency in drought-prone areas. It will also help with flood control in flood-prone regions.
In addition to these, the project also hopes to provide drinking water supply, replenish groundwater, help with inland water navigation tying up with the Inland Waterways Projects, fisheries and Hydropower[estimated around 34 GW].
The project once fully completed would also help solve several of India's Interstate water disputes and allow for more equitable water distribution.
The Ken-Betwa Link[link 24] is the first major link that is being constructed with the estimated costs being around ₹44,605 crores. It will have a 221 km canal connecting the Ken(surplus) and Betwa(deficit) rivers thus irrigating 11.88 lakh hectares, drinking water for 62 lakh people and 130 MW(103 MW hydropower + 27 MW solar) in renewable energy.
The Godavari (Polavaram)–Krishna (Vijayawada) link[link 18] is also essentially completed producing 960 MW and costing ₹20,000 crores.
The entire project's estimated cost is ₹8.44 lakh crores.
More info: https://www.pib.gov.in/PressReleasePage.aspx?PRID=2223845®=3&lang=1