QUES . Discuss the ecological and economic challenges of river linking in India.
HINTS:
National River Linking Project (NRLP), proposes to connect 14 Himalayan and 16 peninsular rivers with 30 canals and 3,000 reservoirs to form a gigantic South Asian Water Grid. The initial plan to interlink India’s rivers came in 1858 from a British irrigation engineer, Sir Arthur Thomas Cotton.
Components of National River Linking Project (NRLP)
1 . Himalayan component: This component aims to construct storage reservoirs on the Ganga and Brahmaputra rivers, as well as their tributaries in India and Nepal. It will connect, 1) the Ganga and Brahmaputra basins to the Mahanadi basin, and 2) the Eastern tributaries of the Ganga with the Sabarmati and Chambal river systems.
2 . Peninsular component: It includes 16 links that propose to connect the rivers of South India. It envisages linking, 1) the Mahanadi and Godavari to feed the Krishna, Pennar, Cauvery, and Vaigai rivers, 2) the Ken river to the Betwa, Parbati, Kalisindh, and Chambal rivers, 3) West-flowing rivers to the south of Tapi to the north of Bombay, and 4) Linking some west-flowing rivers to east-flowing rivers.
Objective behind interlinking of rivers
As per the govt, the project is needed to meet increasing water requirement in the country. Overall, the NRLP envisions the transfer of water from water ‘surplus’ basins (perennial Himalayan rivers) where there is flooding to water ‘deficit’ basins (rain-fed peninsular rivers) where there is drought/scarcity, through inter-basin water transfer projects.
Environmental or ecological challenges of river linking
There is a knowledge gap between the claimed benefits and potential harm to the environment and ecology.
The ecology of every river being unique, so letting the waters of rivers mix, may affect biodiversity. Also, when most of the rivers in the country are polluted, this may cause mixing of a less polluted river with a more polluted one.
For river interlinking, the construction of numerous small dams and barrages is needed, which will submerge vast stretch of forests. Also, deforestation will take place on a large scale for executing the project.
The water deficit region will get sufficient water but there will be sudden changes in habitat also, such as soil moisture and vegetation growth, which may negatively impact the organisms.
The construction of the canals and submergence of the area will decrease the habitat of the wild organisms which may decrease the biodiversity.
Lack of fresh influx of water in estuaries, deltas and ocean may lead to damage of the marine ecosystem.
The frequency of landslides and earthquake-like disasters may increase.
Economic challenges of river linking
NRLP is a highly capital-intensive project. In 2001, the total cost for linking the Himalayan and peninsular rivers was estimated at Rs 5,60,000 crore, excluding the costs of relief and rehabilitation, and other expenses. This cost is likely to be substantially higher now, and the cost-benefit ratio might no longer be favourable.
Huge capital is needed for constructing dams and canals. Also, course of most of the rivers changes over time, thus the linking of rivers will be challenging and will cost much.
Reports points out that Climate change will cause a meltdown of 1/3rd of the Hindu Kush Region’s glaciers by 2100. So, the Himalayan rivers might not have ‘surplus water’ for a long time. Also, considering this, investing billions of money in the interlinking of rivers might yield benefits only for a short time.
Thus, the river linking project is a great challenge and an opportunity to address the water issues arising out of climate change. The long-term solution to water scarcity lies in making the interlinking of rivers project work by building a network of dams and canals across the length and breadth of the country. However, interlinking has to take place after a detailed study so that does not cause any problem to the environment or aquatic life.
