As it oozes through the city of Delhi, the holy river Yamuna is a vile tract of faecal sludge. From its foul-smelling banks, fishermen cast

their nets and haul in a few surviving spiny fish. A group of young men dive, retrieving coins lodged in the river’s silty bottom. And nearby, a man empties a burlap sack of ashes — the dusty remains of a family member — into the slime. This 22-kilometre stretch of water is one of Asia’s most polluted: 3.5 billion litres of sewage, much of it untreated, makes its way into the river every day.

Of more concern than the quality of Delhi’s water, however, is the availability of water at all. Even in the better neighbourhoods, it is com-mon to go several unpredictable hours per day without supply. When the water does flow, up to 40% of it is lost through leaky pipes. Because of the city’s notoriously poor municipal water supply, about one-quarter of Delhi’s 15 million people rely on privately-dug wells, a practice that itself is lowering the water table.

Delhi is a harbinger of the country’s loom-ing water crisis. Today, India has enough water to provide each of its citizens with just over 1,800 cubic metres each year — enough to

cover the 1,700 cubic metres each individual is estimated to need annually both directly, for drinking and hygiene, and indirectly, to grow the food that person consumes. But as the country’s population continues to grow the demand for water will rise. Most of the demand will come from agri-culture: irrigation already accounts for more than 90% of the country’s freshwater consumption, and much of it is channelled to thirsty crops such as rice. Over the next 20 years, the World Bank predicts that India’s per capita water availability will drop below 1,000 cubic metres, well below the 1,700 cubic metres deemed necessary for survival. By the middle of the century, when the population is expected to stabilize somewhere between 1.5 and 1.8 bil-lion, the United Nations Environmental Pro-gramme estimates that India will require 30% more water than it can currently supply.

Already farmers in the arid western states such as Rajasthan and Gujarat as well as some of the northeastern states, including West Bengal, are running into trouble as the water table drops from over use. In Delhi too,

problems are exacerbated by the demands of agriculture — upwards of 85% of the water from the Yamuna basin has been redirected for irrigation, reducing the river’s capac-ity to recharge the city’s natural aquifers.

Yet the country’s water is likely to be diverted further in future, if the country’s planners get their way.

Diversionary tacticsConfident in its ability to find an engineering solution to every prob-lem, India is considering an ambi-tious plan to link the majority of its major river basins through a vast network of canals, diverting billions

of litres from the country’s more water-rich river basins to those that are water-deprived. Directed by India’s National Water Develop-ment Agency (NWDA), the first canal of the interlinking rivers project may get underway as early as this year.

What is not clear, however, is whether the solution will improve the situation. Very lit-tle information is publicly available on the scheme’s potential environmental impact or on the true extent of the predicted water

India’s population is growing, and its water supplies are not keeping pace. Can an ambitious scheme to connect up the country’s rivers slake the nation’s deepening thirst? Daemon Fairless investigates.

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shortage. “There are no documents that openly establish the economic, social and environmental justifiability of the proposal for [the interlinking of riv-ers],” according to Jayanta Bandyopad-hyay, a specialist in development and environmental policy at the Indian Institute of Management Calcutta and a member of the National Civil Society Commit-tee on the Interlinking of Rivers in India (NCSCILR), a group of aca-demics, researchers and policy advisers who oppose the plan. “The interlinking plan has the potential to wreak environmental havoc on a scale so far unseen in the subconti-nent,” says Vedaraman Rajamani, a geologist at Jawaharlal Nehru University’s School of Environmental Sciences in New Delhi.

Wasted waterIndia is not, at first glance, a particularly water-poor country. It receives around 1,170 millimetres of rainfall a year. The problem lies in the variable distribution of precipita-tion: whereas northeastern Meghalaya, one of India’s wettest states, gets an average of 2,818 millimetres per year, Rajasthan, in its driest years, can get as little as 100 millimetres. The logic behind the interlinking project, accord-ing to the few documents and press releases that are available, is to capture the “surplus water” that otherwise flows wastefully to the sea, and reroute it to where it is needed for irrigation and hydroelectric power.

The idea of linking rivers dates back to the mid-nineteenth century, when Arthur Cotton, a British general and engineer, proposed a series of canals for inland transportation. The current reincarnation came about after a 2002 battle in the supreme court between the states of Tamil Nadu and Kar-nataka over access to irrigation waters from the Kaveri River. As part of their ruling, the judges mandated that the interlinking rivers project — little more than an NWDA research concept at the time — be completed by 2012. The decision seemed to be largely oblique to the legal case in question and left observers puzzled. “It was a big blow for many of us that the court intervened in this way,” says Yoginder Alagh, former minister of both Power and Planning and Science and Technology and a member of the NCSCILR. The Ministry of Water Resources, which con-trols the NWDA, did not respond to Nature’s repeated requests for an interview about the interlinking project.

The unusual way in which the project was mandated, and the sometimes impenetrable nature of India’s government bureaucracies, mean that noone is clear precisely what will be involved, or when. But overall, the proposal is to link 46 rivers from most of the country’s major river basins through a 10,000-kilome-tre long network of 30 canals, several of which

will intersect with more than one river (see ‘Linked up’). The project, which is estimated to cost about US$200 billion, also includes the construction of 32 major dams. “If undertaken, it would be the single largest engineering project anywhere in the world,” according to Ashok Khosla, chairman of the Development Alternatives Group, a non-profit organiza-tion based in New Delhi that

opposes the plan. The vast scale of the project is a source of

some pride. Jawaharlal Nehru, India’s first prime minister, famously referred to large multi-purpose dams as the “temple[s] of modern India”. At its independence in 1947, India had only about 300 major dams; by 2000, the number of these modern temples

had exceeded 4,000. That puts it in third place for the greatest number of dams,

after China, which boasts some 86,000 and the United States, which

has about 79,000. In this same spirit of national advancement, the interlinking

project will put an additional 35 million hec-tares under irrigation — close to doubling the area fed by major irrigation projects in 2003, according to a press statement by Suresh Pra-bhu, then chairman of the NWDA Taskforce on Interlinking Rivers. In doing so, he stated, the project will combat drought in 250,000 hectares across the country, and reduce flood damage along the Ganges and Brahmaputra rivers basins by some 20–30%. The perennial flooding of these two rivers, which together carry 60% of the nation’s freshwater resources, last year destroyed $850-million worth of damage and killed more than 1,000 people.

Mukuteswara Gopalakrishnan, secretary-general of the New Delhi-based International Commission on Irrigation and Drainage and former coordinator of the Taskforce on Inter-linking Rivers, says that the project could also supply about 34,000 megawatts of hydro-power — roughly doubling the current level of hydropower, which lies at just over 25% of the country’s current electricity needs. “This is the kind of project any developing country would like to have,” Gopalakrishnan says. Government proponents have also argued that the scheme will be beneficial to river ecology because waterways that typically shrink in the dry season would have water pumped into them year round.

Superficial informationThe NWDA has published feasibility reports for 14 of the 30 proposed canals on its website. The reports are the only govern-ment-supplied data made publicly available on the project and they detail the pros and cons of each proposed canal. They con-tain few verifiable data and do not cite any research studies; the sections that address putative ecological impacts do little more than state the total area to be submerged by damming, estimate the number of people

“There are no documents that openly establish the justifiability for interlinking rivers.”— Jayanta Bandyopadhyay

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LINKED UPIndia’s interlinking rivers project aims to connect the country's rivers through a vast network of 30 canals (red). The Ken–Betwa link (arrow) is the closest to being built.

that would be displaced and briefly list some of the local flora and fauna.

Unsurprisingly for a scheme of such magni-tude and obscurity, the project has many out-spoken critics. A key point they raise is that the concept of surplus water used by the project is misleading, because it ignores the essential ecological role played by run-off and flooding. “It’s an entirely anthropocentric definition,” Rajamani says. “It does not take into account the fact that these ecosystems developed under the constraints of monsoon flooding and peri-ods of drought.” Bandyopadhyay and Shama Perveen, also from the Indian Institute of Management Calcutta, made this argument in one of the first public critiques of the project. In a 2004 article in the online journal India Together, they lambasted India’s central gov-ernment as having taken a “reductionist view” — one that “ignores the whole set of eco-system services provided by water”.

Proceed with cautionIn August 2005, Rajamani published his own opinion piece in The Hindu, one of India’s leading national news-papers, criticizing the national plan as having an unsophisticated understand-ing of the subcontinent’s hydrological cycle. In the article, Rajamani said that the annual floods the government planned to mitigate were important in removing agricultural toxins from farm land, depositing soil nutrients and recharging groundwater in key agricultural areas. He argued that such a massive re-working of India’s rivers is likely to have some unexpected rami-fications, including deleterious effects on the nation’s coastal ecosystem and even, potentially, alterations in the monsoon cycle. “It was more or less speculation,” says Rajamani, “but my point was that to proceed with such a plan without taking such things into account and doing some very detailed studies would be suicidal”.

Rajamani’s article caught the atten-tion of then president Abdul Kalam, a strong proponent of the interlinking

plan. Kalam surprised Rajamani with a phone call in which he asked if there were any data to back up Rajamani’s concerns about the monsoon. There were not — but prompted by Kalam’s interest, Rajamani invited several Indian Earth scientists to a one-day meeting in Bangalore in October 2005. Little more than an impromptu brainstorming session, it was the first scientific discussion of the project’s environmental ramifications outside government walls. It was also one of the last.

The group concluded “based on a simplis-tic interpretation of presently available data”, that attenuation of water flow into the Bay of Bengal due to river diversion could very well affect the volume, duration and spa-tial distribution of the monsoon cycle1. The freshwater run-off that flows from India’s east coast forms a 10–20-metre layer of water over much of the northern Bay of Bengal. This blanket of low-saline water is thought to play a part in the formation of the monsoon clouds which, in turn, deposit most of India’s freshwater on its landmass. The group’s con-clusions make sense, says Edward Maltby, a specialist in wetland management at the Uni-versity of Liverpool’s Institute for Sustainable Water, Integrated Management & Ecosystem Research in the United Kingdom. “There are likely to be many other potentially significant

consequences,” he adds, “such as an impact on coastal and marine ecosystems as well as the functioning of land-based ecosystems.”

The main point of the report, says Raja-mani, was to show that researchers are not being included in the assessment process: but like other public critiques, the report elicited no public response from the NWDA and lit-tle independent follow-up research has been done since.

Classified informationThe group also criticized the fact that there are no publicly available estimates of river flow from India’s Himalayan rivers. Such data are guarded by the government because water access, which is shared with Pakistan, China, Bangladesh, Bhutan and Nepal, is a major source of political tension. These

figures are absent from the feasibil-ity reports, making it more or less impossible for outside scientists to estimate how much water would be left flowing in India’s rivers if they were to be diverted. This is a criticism shared widely among environmen-tal scientists. “Even today, river-flow data are classified information,” says Brij Gopal, chief editor of the Interna-tional Journal of Ecology & Environ-mental Sciences and a hydrologist at Jawaharlal Nehru University.

Rajamani says that one of his on-going frustrations is that environ-mental science in India is more or less ignored by government planners. Whereas disciplines such as physics and engineering are highly respected, says Rajamani, “environmental science is Dalit science — that is, it is like our untouchables: unseen and unheard”. As such, he says, river planning and water management have traditionally fallen into the hands of engineers and government technocrats who are not always qualified, nor necessarily con-cerned with the environmental impact of large-scale water projects. Gopal is even more vociferous in his criticism. “India’s environmental science — or at

“Environmental science is Dalit science — that is, like our untouchables.” — Vedaraman Rajamani

It never rains but it pours: vast geographical differences in India’s rainfall make it difficult to manage the water supply.

“This is the kind of project any developing country would like to have.” — Mukuteswara Gopalakrishnan

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least its wetland science — is driven by policy rather than the policy being driven by sci-ence,” he says. If there’s one source to blame for the current state of India’s rivers, says Gopal, “it’s the government engineers”.

All this debate could prove academic if the project never materializes. No construction has yet begun, although the first of the 30 pro-posed links — a 230-kilometre canal between the river Ken in Madhya Pradesh and the river Betwa in Uttar Pradesh — is moving forward. The two states signed a memorandum of understanding with the central government in 2005. Gopalakrishnan, who still acts as a government consultant on the interlinking project, says that a detailed project report has been drawn up and that he is fairly sure that it will be approved in the next year.

Driving factorsThis doesn’t necessarily mean that all the links will go ahead. After talking with engi-neers from the Central Water Commission and the NWDA last summer, Kanchan Cho-pra, director of the Institute of Economic Growth at Delhi University, says she thinks that the NCSCILR’s public criticism has cre-ated enough pressure to slow the plan down somewhat. “Rational dissent seems to have tempered the government’s enthusiasm,” says Chopra. “It may be dying a natural death.” But Gopalakrishnan says that this is wishful thinking on the part of those who oppose the plan. “It is almost inevitable,” he says, that the entire project will go through. Warnings of India’s impending water shortage seem to have endowed the project with a sense of urgency.

But some experts say that the water crisis seems more alarming that it really is, partly because accurate estimates of water avail-ability are hard to come by. Hubert Savenije, a hydrolo-gist at Delft University of Technology in the Neth-erlands, distinguishes two types of fresh water avail-able for use2. ‘Blue water’ — that from rivers, lakes and streams — feeds crops by irrigation. It can be vital during dry stretches in the growing season, but accounts for only about 20–30% of the actual amount of fresh water that enters food production each year. The rest comes from ‘green water’, the rain water stored in the soil that is absorbed directly by food plants, and which according to Savenije produces more than 60% of the world’s staple food production.

The problem arises because estimates of water consumption made by bodies such as the United Nations, generally include both

blue water and green water. But estimates of water availability tend to ignore the contribu-tion of green water because it is quite a new concept — a gross oversight, in Savenije’s opinion. This is a major problem in India, where there are no accurate estimates of green water. The disparity gives the false impression that demand is hugely outstrip-ping supply, he says.

That is not to say that there is no need to manage water better, just that the ways to do it — those that the government is neglecting in its focus on interlinking — might not have to be so drastic. Alagh, who has been heavily involved with planning India’s various irriga-tion schemes, says that increasing the overall water supply will not, as the project’s propo-

nents say, boost agricultural productivity. He points out that although increasing irrigation led to an enormous boost in crop productivity during the 1970s and 80s, it has actually resulted in a drop in overall crop yield in the past five or so years, in

part because of mismanagement of new irri-gation systems.

Alagh says that the solution lies in better management of existing water resources, rather than importing water for irrigation. A simple way to do this is by using large tanks to collect rainwater, which is later supplied to fields during dry periods. Indian irriga-tion practices could also be made more effi-cient. A lot of water is lost in evaporation or through drainage from unsealed irrigation canals, and the common practice of flood

irrigation is wasteful compared with drip irri-gation, which supplies water directly to the plant’s roots. But the water used for irrigation is free, so Indian farmers have little incentive to adopt more economical methods.

Savenije for one feels that the Indian gov-ernment has lost sight of the simplest solu-tion: to grow more crops in the wet areas and ship them to the dry ones, rather than transporting the water itself. That’s because crops are many times lighter, and therefore cheaper to transport, than the water used to grow them. But improving food distribution is a formidable challenge because of the lack of local transportation, the poor condition of much of India’s rural infrastructure and inequitable rural markets. But, says Savenije, “it is certainly no more of a challenge than re-shaping the country’s river network.”

On the banks of Delhi’s holy river, visi-tors seem oblivious to the sorry state of the country’s water. Families visit the ghats along the Yamuna’s banks where, for a few rupees, they pay a small boy to swim out into the slime and launch religious offerings of sweet-meats, fruit and flowers downstream on a small straw mat. They sail downstream, to an unknown destination. India, and its entire dwindling water supply, face a simi-larly uncertain future. ■

Daemon Fairless is last year’s winner of the IDRC Nature fellowship.

1. Rajamani, V. et al. Curr. Sci. 90, 12–13 (2006).2. Savenije, H. Phys. Chem. Earth B 25, 199–204 (2000).

See Editorial, page 253.For more on water, see http://www.nature.com/news/specials/water/index.html.

“India’s environmental science is driven by policy rather than the policy being driven by science.” — Brij Gopal

Dirty business: India’s growing population is expected to make water supplies scarce.

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