India has only 4 per cent of the world’s renewable water resources while population share of India is about 18% of World. The average annual precipitation in India is estimated to be 4,000 BCM (billion cubic meters), out of which the average precipitation during monsoon (June-September) is estimated at 3,000 BCM. This uneven distribution of rainfall causes drought and flood in most of states resulting in numerous human and economic loss to country.
The average annual run off in the rivers is estimated to be 1,869 BCM. Out of the above, the estimated utilizable surface water resource is 690 BCM which is only one third of the total potential. Agricultural sector is highly stressed and contains more people than required i.e. disguised employment which should be diverted to non farming activities as these activities require less land and can generate more income such as fish farming.
It is projected that availability of water for agricultural use in India may be reduced by 21 percent till 2020, resulting in decline of yield of irrigated crops, especially rice resulting in price rise and shortage of food for the poor masses. In the total 329 million hectares (mha) of geographical area of the country, the total area under cultivation is about 194 mha, out of which net sown area is only about 140 mha. Only about 66 mha, i.e., 47.6 per cent of the net sown area, is reported as irrigated. There is a need to bring more cultivated area under assured irrigation to increase agriculture productivity and production. Moreover 40 million hectares is prone to floods and 68% of the area is susceptible to drought.
What is it?
Inter Linking of Rivers (ILR) is considereded to be the panacea to India’s predicament including drought, floods, food security, tourism and much more. It can be achieved through conservation of the abundant monsoon water by storing it in reservoirs, and delivering this water using rivers inter-linking project to areas over times when water becomes scarce. Beyond water security, the project is also expected to offer potential benefits to transport infrastructure through navigation as well as broaden income sources in rural areas through fish farming. It is basically diversion of water from water surplus basins to water deficit basins/areas. Broadly it has been divided into 2 components viz. Himalayan Rivers Development and Peninsular Rivers Development.
Himalayan Rivers Development Component envisages construction of storage reservoirs on the principal tributaries of Ganga and Brahmaputra rivers in India, Nepal and Bhutan. This project also includes interlinking of river systems to transfer surplus flows of the eastern tributaries of the river Ganga to the west, apart from linking of the main Brahmaputra and its tributaries with Ganga and with the river Mahanadi.
Various proposed links of Himalayan Rivers are:
1. Manas –Sankosh – Tista – Ganga 2. Kosi – Ghagra 3. Gandak – Ganga 4. Ghagra – Yamuna 5. Sarda – Yamuna 6. Yamuna – Rajasthan 7. Rajasthan – Sabarmati 8. Chunar – Sone Barrage 9. Sone Dam – Southern Tributaries of Ganga 10. Ganga – Damodar – Subernarekha 11. Subernarekha – Mahanadi 12. Kosi – Mechi 13. Farakka – Sunderbans 14. Jogighopa – Tista – Farakka
Peninsular Rivers Development Component is divided into four major parts viz.
1.Interlinking of Mahanadi-Godavari-Krishna-Cauvery rivers and building storages at potential sites in these basins – This part involves interlinking of the major river systems where surplus from the Mahanadi and the Godavari are intended to be transferred to the needy areas in the south through Krishna and Cauvery rivers.
2.Interlinking of west flowing rivers, north of Bombay and south of Tapi – This scheme envisages construction of as much optimal storage as possible on these streams and interlinking them to make available appreciable quantum of water for transfer to areas where additional water is needed. The scheme provides for taking water supply through canal to the metropolitan areas of Mumbai. It also provides irrigation in the coastal areas in Maharashtra.
3.Interlinking of Ken-Chambal, The scheme provides for a water grid for Madhya Pradesh, Rajasthan and Uttar Pradesh and interlinking canal backed by as many storages as possible.
4.Diversion of other west flowing rivers – The high rainfall on the western side of the Western Ghats runs down into numerous streams which discharge into the Arabian Sea. The construction of an interlinking canal system backed up by adequate storage could be planned to meet all requirements of Kerala and also for transfer of some water towards east to meet the needs of drought affected areas.
Various proposed links of peninsular Rivers are:
Mahanadi (Manibhadra) – Godavari (Dowlaiswaram) 2. Godavari (Inchampalli) – Krishna (Pulichintala) 3. Godavari (Inchampalli) – Krishna (Nagarjunasagar) 4. Godavari (Polavaram) – Krishna (Vijayawada) 5. Krishna (Almatti) – Pennar 6. Krishna (Srisailam) – Pennar 7. Krishna (Nagarjunasagar) – Pennar (Somasila) 8. Pennar (Somasila) – Cauvery (Grand Anicut) 9. Cauvery (Kattalai) – Vaigai – Gundar 10. Ken – Betwa 11. Parbati – Kalisindh – Chambal 12. Par – Tapi – Narmada 13. Damanganga – Pinjal 14. Bedti – Varda 15. Netravati – Hemavati 16. Pamba – Achankovil – Vaippar
Advantages of ILR are
1.India will require about 450 million tonnes of grain per annum to feed the population of over 1.5 billion in 2050. To meet this requirement, the country needs to expand its irrigation potential to 160 million hectares for all crops by 2050. This can be made possible through the interlinking of rivers.
2.Floods and Drought co exist in large parts of the Country. ILR will transfer excess water from flood-ravaged states to water-scarce regions. By this, it will provide irrigation to about 35 million hectares in water-scarce western and peninsular regions.
3.India currently stores only 30 days of rainfall, while developed nations strategically store 900 days worth of water demand in arid areas river basins and reservoirs. India also relies excessively on groundwater, which accounts for over 50 percent of irrigated area. With ILR this situation can be improved.
4.India needs infrastructure for logistics and movement of freight. Using connected rivers as navigation is a cleaner, low carbon footprint form of transport infrastructure, particularly for ores and food grains.
5.ILR is expected to generate additional hydropower of about 34,000 MW. Currently available hydropower is 85,000 MW.
6.About 80% of Indian diets are deficient in proteins which can be economically viable only by fish farming (healthy by-product of ILR).
7.It will ensure food security, employment, boost crop output and farm income, salinity control, pollution control, and multiply benefits through backward and forward linkages.
8.It will help to meet Global Carbon Emission Norms. India will be able to shift from petrol/diesel cars to electric ones.
Disadvantages of ILR are
1.The current cost of the project is Rs 11 lakh crore, twice the estimate of 2002 which the government is putting forward. This huge fund will be mobilized through cutting on social sector spending as the government cannot increase taxes and duties that can hamper economic growth.
2.The feasibility of the project has not been studied in detail, nor has its economic, social and ecological implications. There is no social impact assessment done on the displacement of people and on the livelihood of the people who are living in these areas.
3.Loss of biodiversity and forests downstream of donor river will occur.
4.It has been argued that there is no concept of deficit and surplus.
5.Alternative options such as watershed development, rainwater harvesting, ground water recharge, optimizing existing infrastructure and cropping methods have not been explored fully.
6.Regime of river pairs like Ken-Betwa and Godavari-Krishna are almost same as they receive rainfall at same time and flow through similar region. Thus if one river is dry or flooded then at the same time, similar phenomenon is showed by other river.
7.A canal is not a river and it cannot support an ecosystem.
8.There is a big problem of desilting and there is no clarity on where the silt will be actually dumped.
9.The water flowing into sea, instead of being wastage performs a key ecological function of preventing salination of coastal areas by acting barrier in way of sea water.
10.A major issue in India vis-a-vis river-linking is that water is a state subject. States that have surplus water are not ready to give it to other states.
11.The Himalyan component calls for building dams in Bhutan. In at least some inter-link projects, neighboring countries like Bangladesh may be affected. This will need international collaboration and thus huge potential for logjam.
Examples from where to learn –
In Egypt due to construction of Ashwan high dam, Schistosomiasis endemic spread because canals acted as ideal home for snail vector but now with technological advancements new designs are developed which can prevent this, Also there was increased salinity (less fertility i.e. requirement for more artificial fertilizers).
In case of Mississippi River, United States canals led to mismanagement (water wastage) because it is a natural phenomenon that when a resource is suddenly available in abundance, it is human tendency to waste it. Thus strong legal measures must be taken to monitor wastage.
- The linking of Godavari and Krishna was completed in 2015. The next project being taken up is Ken-Betwa link.
- Feasibility Studies of following two links, i.e. (Indian Portion) Ghaghara-Yamuna Link, Sarda-Yamuna Link are completed.
National Water Development Agency : National Perspective Plan( NPP)
State of Indian Agriculture 2015-16 , Directorate of Economics and Statistics, New Delhi
Agriculture Policy: Vision 2020, IARI