The dry reservoirs -- despite an average monsoon -- of south Karnatakas Cauvery basin illustrate Indias rainfall trends over 65 years: A drop in moderate monsoon rainfall and an increase in extreme events, such as deluges and dry spells, as IndiaSpend reported in April 2015.
The dry reservoirs — despite an average monsoon — of south Karnatakas Cauvery basin illustrate Indias rainfall trends over 65 years: A drop in moderate monsoon rainfall and an increase in extreme events, such as deluges and dry spells, as IndiaSpend reported in April 2015.
Now, a new analysis of rainfall data reveals that monsoon shortages are growing in river basins with surplus water and falling in those with scarcities, raising questions about India’s Rs 11 lakh crore ($165 billion) plan to transfer water from “surplus” to “deficit” basins.
Water in surplus basins — such as the Mahanadi and other major west-flowing rivers in western India — fell more than 10 per centover a quarter-century (1951-1975 and 1976-2000) and increased by more than 10 per cent in the Indus, the Ganges and some east-flowing rivers down south, according to a study in PLOS One, an open-access global journal.
“Narrowing disparities in the water yield of Indian river basins call for an immediate reassessment of inter-basin water transfer plans,” Sachin S. Gunthe, corresponding author of the study and associate professor, department of civil engineering, Indian Institute of Technology (IIT) Madras, told IndiaSpend.
At 2001 prices, 30 inter-basin transfers — through a proposed network of canals, dams, aqueducts and pumping stations — were budgeted at Rs 560,000 crore ($124 billion at 2001 exchange rates). In April 2016, Water Resources Minister Uma Bharati revised the estimate to Rs 11 lakh crore, almost double the estimate made 15 years ago — a sum equivalent to 44 times India’s agriculture budget or 1.6 times all government spending in 2015-16.
The first river-linking project — meant to bring the waters of the Ken river 231 km from Daudhan in Madhya Pradesh to drought-ridden Bundelkhand in western Uttar Pradesh — was cleared in September 2016 amidst controversy, since it would mean submerging 100 sq km of central India’s Panna tiger reserve.
Despite the new evidence that changing monsoon patterns may require a review of the inter-basin water-transfer programme, a government spokesperson questioned the study’s interpretations, while India’s environment minister acknowledged to IndiaSpend that since there were “many conflicting opinions”, the Ken project would test the waters.
Independent experts advocated caution before going ahead with a multi-billion-dollar effort that has led to ecological upheavals in other countries, and in one instance partially reversed in Australia with dams being retrofitted. Globally, linking rivers is now a contentious issue.
The controversy over river-linking begins with the financial costs.
With incomplete cost estimates, accurate cost-benefit analysis is difficult
The original $124 billion estimate of 30 inter-basin transfers excluded key expenses, such as the cost of dams, relief and rehabilitation and electricity need to pump water, according to this July 2016 report (co-written by former Planning Commission member Mihir Shah) on restructuring the Central Water Commission and the Central Ground Water Board.
Several cost estimates were missing.
Environmentalists have predicted other possible adverse environmental outcomes of the proposed project-based on reason and/or global experiences-such as:
* Interlinking river basins could adversely impact the monsoon, V Rajamani, professor emeritus, Jawaharlal Nehru University, wrote in a 2006 comment in Current Science, an Indian scientific journal. If the water of India’s east-flowing rivers is diverted so that less water flows into the Bay of Bengal, it could set off a cascade of events-including low salinity, which keeps sea-surface temperature “high”, above 28 deg C and thus creates low-pressure areas-and intensifies the monsoon over much of the sub-continent.
* Damming India’s east-coast rivers to take their water westwards will curtail downstream flooding and thereby, the supply of sediment-a natural nutrient-destroying fragile coastal ecosystems and causing coastal and delta erosion, predicted one report.
The design of India’s inter-river-basin water transfer project may also be flawed. “Given the topography of India and the way links are envisaged, they might totally bypass the core dryland areas of Central and Western India, which are located on elevations of 300+ metres above mean sea level,” said the Mihir Shah committee report.
“Instead of repeating the mistakes of other countries, India must learn from failed river basin interlinks,” said Shah, economist and former Planning Commission member, also co-founder of Samaj Pragati Sahayog (Social Progress Cooperative), an advocacy for livelihoods security.
Why linking river basins would reduce groundwater recharge
India meets 80 per cent of its water needs through groundwater, which also waters 60 per cent of irrigated area. Close to 60 per cent of the urban water supply and 85 per cent of the rural water supply is groundwater, said Himanshu Thakkar, coordinator, South Asia Network on Dams, Rivers and People, an advocacy.
As a result, groundwater levels across India have plummeted and quality has deteriorated. In the decade ending in January 2016, water levels declined in 65 per cent of the country’s wells, according to a 2016 Central Ground Water Board report.
“Think of river basin interlinking only after exhausting the local potential for harvesting rain, recharging groundwater, watershed development, introducing better cropping patterns (non water-intensive crops) and methods (such as rice intensification), improving the soil moisture-holding capacity and saving and storing water,” said Thakkar. “We still haven’t done that.”