Fragile ecosystems

Print edition : April 20, 2012

Kerala's rivers are part of unique, sensitive ecosystems, which would be disturbed by the river-linking project.

in Thiruvananthapuram

Kerala is a shoestring-like piece of land tucked away between the Western Ghats and the Arabian Sea. It has four distinct physiographic zones, the highlands, the midlands, the lowland plain, and the extremely narrow coastal plain.

South of Kochi, central Kerala is an enchanting landscape, a region of five rivers originating in the Western Ghats and flowing rapidly through the undulating plains to drain into the Vembanad wetland system. The Vembanad deltaic region includes one of the longest lakes in India, the lower reaches of the five rivers, and a complex system of backwaters, marshes, lagoons, mangrove forests, reclaimed land, paddy fields, coconut palms and a network of canals.

A sizable portion of this coastal wetland zone lies at or below sea level. It is a thickly populated region, a major part of which Kuttanad, with 54 villages spread over three districts is known as the rice bowl of Kerala and is famous for its distinctive patterns of cultivation, sometimes carried out up to two metres below sea level, with the fields being prone to floods as well as salt water intrusion from the sea.

The region is also famous for the unique formation of mud banks, known as chakara, during the monsoon, when the mud and silt washed down by the rivers help form nutrient-rich havens on the coast for fish and prawns that come seeking sanctuary from the rough sea, and offering a rich harvest to fisherfolk. The Vembanad backwaters is today among the most sought-after tourism destinations in India. Visitors are often bowled over by the breathtaking beauty of the place and wonder at the abundance of water in and around it. Therein is a problem. They all see a river, or a lake or the backwaters, merely as water' and go home with an idea of abundance. But they fail to see them as unique ecosystems, sensitive and fragile and in need of extreme care, Professor K.G. Padmakumar, Associate Director of the Kerala Agriculture University's Regional Agriculture Research Station at Kumarakom, told Frontline.

He was responding to questions on how the proposed trans-basin diversion to Tamil Nadu of the waters of the Pamba and the Achankovil, two of the five rivers that drain into the southern Vembanad wetland system, would affect Kerala, a State widely believed to have 41 rivers and hence a surplus of water.

Continuous freshwater flow from the five rivers (a sixth one, one of the tributaries of the Periyar also joins the Vembanad backwater system in its lower reaches) is crucial for the Vembanad region, which was declared a wetland of international importance under the Ramsar Convention in November 2002. The area, however, has been under increasing ecological stress over the years, a target of intense human interventions, especially for agriculture and tourism.

The result has been extreme fertilizer pollution from agricultural fields, and pollution caused by organic, inorganic and toxic materials locally generated or brought in by the rivers, aggressive spread of invasive plant species such as water hyacinth, choked waterways and poor drainage, loss of fish and migratory water fowl species and population, increasing intensity of flooding, shortage of potable water, and proliferation of water-borne parasites and predators affecting human health.

The proposal for diversion of the Pamba and the Achankovil is viewed with a lot of concern here. The Vembanad lake has today become a dumping yard, and the natural flushing mechanisms have long been hindered or proved inadequate. There is concern that such a project is even being considered without taking into account the visibly decreasing river flow during most parts of the year, said Dr S. Leena Kumari, Professor and head of the Rice Research Station, Moncombu, in Alappuzha district.

An inter-State transfer of the waters of the Pamba and Achankovil will be suicidal to the interests of Kuttanad, which is already facing an ecological disaster. The fact is Kerala has no surplus water to transfer even from one basin to another within the State. The Kuttanad package recently announced by the Union government itself is meant to find solutions to the ecological crisis in Kuttanad. One of its major concerns is how to find more water to maintain the ecological balance in Kuttanad, said Chief Secretary K. Jayakumar, who has for long been in charge of inter-State water issues.

The refrain, initially raised by the scientific community, is now a common one in the State, ever since Tamil Nadu began to insist on speedy implementation of the Pamba-Achankovil-Vaippar (PAV) project proposal, one among the eight river-linking projects on the priority list for which the National Water Development Agency (NWDA) had prepared feasibility reports in 1995.

According to Prof. Padmakumar, it is important to understand that the rivers of Kerala cannot be termed rivers in the real sense, as they are diminutive rivers, compared with those in many other parts of India that are 1,000 km or longer. They are also not perennial rivers, being monsoon-fed, and many of them go mostly dry during the summer months. Moreover, Kerala's unique topography means that all the rain that falls in the highlands flows to the sea in a matter of hours.

But though the State has only a small share of the country's geographic area, it is a biodiversity hot spot. Nearly 22 per cent of the plant diversity of India is in Kerala, and 35 per cent of freshwater fish diversity of the country is found in the rivers of the State. It is surprising how everyone wishes away scientific facts when they moot such diversion schemes. We treat the river merely as a body of water, but it is a unique ecosystem. The Vembanad lake, located below sea level, plays an important role in determining the water table of the midlands and the highlands. Do we not have an obligation to protect such sensitive ecosystems in the national interest? Kerala already has 35 reservoirs; can we afford to disturb the Western Ghats further and build more of them there? he asked.

The proposed project is meant to transfer 20 per cent of what has been found by the NWDA as surplus water of the two rivers to the Vaippar river basin in Tamil Nadu through a nine-kilometre tunnel across the Western Ghats. It involves the construction of three concrete dams, across the Pamba-Kallar at Punnamedu (150 m high and with a storage capacity of 208 million cubic metres, or Mm3), Achankovil-Kallar (160 m high; storage capacity 501.7 Mm3) and Achankovil river (35 m high; storage capacity 33.86 Mm3), a powerhouse for peak power demand at Achankovil-Kallar (installed capacity of 500 MW) and six other powerhouses in the link component (with a total installed capacity of 8.37 MW). The Punnamedu and Achankovil-Kallar dams are to be connected by an eight-kilometre long tunnel. Thus, 634 Mm {+3} of water is to be diverted eventually from the Achankovil-Kallar reservoir through the Ghat tunnel and a 50-km-long main canal that joins the Alagar Odai, a tributary of the Vaippar river in Tamil Nadu. The diverted water is to be used for irrigation in the districts of Madurai, Virudhunagar, Tuticorin and Tirunelveli.

Kerala had been opposing the proposal ever since it was mooted. Among its essential arguments, as explained in a counter-affidavit filed before the court in July 2009, were that: (a) the proposal was based on the erroneous estimation that surplus water is available in the two rivers; (b) Tamil Nadu has no right to demand transfer of waters because the Pamba and Achankovil rivers are fully intra-State rivers, with their entire basins wholly within Kerala; (c) even Parliament has no competency to legislate (by reference to entry 56 of List 1) for transferring water from Kerala to Tamil Nadu; (d) the Kerala Assembly passed a resolution in August 2003, which was binding on the State of Kerala, opposing the transfer of water of the Pamba and the Achankovil to Tamil Nadu; (e) the State Assembly had all legal rights under the Constitution to make laws vesting the waters of intra-State rivers for the benefit of its inhabitants; (f) the waters of the Pamba and the Achankovil are entirely needed for uses in the Vembanad Kol wetland; (g) the proposed transfer of the waters to Tamil Nadu would prejudicially affect the rights and interests of the people of Kerala in the downstream region, and particularly the hydrology of the Vembanad Kol wetland, which is a Ramsar Convention site; and (h) in protecting these wetlands the precautionary principle should apply and that the environmental interest of the Vembanad wetlands system takes precedence over the alleged economic interest of Tamil Nadu.

No surplus water'

According to former State Water Resources Minister N.K. Premachandran, Kerala had informed the NWDA that its conclusions about the surplus availability of water in the Pamba and Achankovil rivers was wrongly based on the annual water availability and that the temporal variations of the river flow were not at all considered by it while forming such conclusions.

The only remedy open before Kerala to overcome the problem of lean season flows is to go in for storage reservoirs. But reservoirs can only be built in the highlands, again a region rich in biodiversity. In the past, Kerala had shared not only water (as part of the Mullaperiyar and Parambikkulam-Aliyar projects) but also such feasible reservoir sites with our neighbouring State and found itself without new storage options when the need arose subsequently within those basins in Kerala. We learned hard lessons from those experiences, he told Frontline, quoting the example of a similar situation caused by the Parambikkulam-Aliyar Project (PAP) in the Chalakudy basin. Kerala had generously granted water and reservoir locations under the PAP to its neighbour and now is left with only 6.5 tmc ft storage in that basin, while Tamil Nadu has 24.5 tmc ft of storage within Kerala, he said.

Moreover, the agreement on the PAP was based on a similar study conducted earlier by the Central Water and Power Commission (CW&PC), which said that there would be surplus water to share with Tamil Nadu in those rivers. Kerala offered water and space to Tamil Nadu for building reservoirs in its territory, but now faces acute water shortage during the summer months and the situation becomes even worse during lean years. In the case of the proposed PAV project, too, the only possible reservoir sites remaining in the Pamba and Achankovil basins are those proposed for the diversion project to Tamil Nadu. Hence it causes concern in the minds of the people of Kerala, the former Minister said.

Dr A.B. Anitha, Head of the Surface Water Division of the Centre for Water Resources Development and Management (CWRDM), Kozhikode, told Frontline that the investigations by the CWRDM in the late 1990s had shown that the basins of four of the five rivers, namely, the Muvattupuzha, the Meenachil, the Manimala and the Achankovil draining into the Vembanad backwater, would have a fresh water deficit for meeting the demands within their boundaries by A.D. 2051. The Pamba has a freshwater flow of 1,208 Mm3, after meeting the projected demands within the basin. However, 4,745 Mm3 of water is required to flush out the present level of pollutants from the Vembanad wetland. Therefore, the Pamba will also have a deficit of 3,537 Mm3, she said.

At the time of writing this report, the Kerala government was yet to decide on what course of action it would take regarding the issue, following the judgment of the Supreme Court on February 27. Mohan V. Katarki, an advocate who had appeared for Kerala in the Supreme Court, told Frontline that the Division Bench had only partly noted the contentions of the State and that Kerala's main argument that the Pamba and the Achankovil are intra-State rivers on which Parliament had no competency to legislate by reference to entry 56 of List 1 for transferring water from Kerala to Tamil Nadu had not been recorded by it.

The effect of the judgment is that it allows one to argue both ways: that since the issue has not been decided, it can be opened again; or that since it has not been decided, it has been decided against the State. It thus creates a grey area, he said.

We feel that the Kerala government has been negligent in informing the court about the real situation on the ground, that the Pamba and the Achankovil are actually water-deficit river basins. There were several occasions in the past years, when the Aranmula boat race, conducted as part of the annual regatta there, had to be postponed because there was no water in the Pampa during the monsoon season. The river course along the road to Sabarimala runs dry frequently; so do the drinking water tanks in the Pamba and the Achankovil rivers, said N.K. Sukumaran Nair, general secretary of the Pampa Parirakshana Samiti, an organisation dedicated to the cause of saving the Pamba.

The initial reaction of Chief Minister Oommen Chandy was that the judgment would not apply to Kerala or its rivers as the order was applicable only to concurring States. Kerala has opposed the interlinking of rivers and the judgment will hence not apply to us, he said.

Premachandran, however, said that it would be wrong for the State to come to such a conclusion because the court seems to have issued a general direction to all the States after hearing the arguments raised by Kerala too. The Supreme Court's direction seems to have reopened the whole issue of the Pamba-Achankovil-Vaippar project, and the State needs to tread carefully if its genuine interests are to be protected, he said.

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