WWW Virtual Library - Sri Lanka
Lunuganvehera and Moragahakande
Will history repeat itself?
(by D. L.
Soon after the change of government in July 1977, a proposal was submitted to the new Minister of Irrigation, the charismatic Gamini Dissanayake, for construction of Lunuganvehera weva, a large new reservoir in the lower Kirindi oya basin. Investigations had been completed and foreign aid was available for early construction. The Minister was not told that technocrats, and the bureaucracy in the Ministry of Irrigation, in preparing the proposal for implementation during the period 1970 - 1977, had ignored directions given by the Prime Minister, as Minister of Planning and Economic Affairs. Those instructions were in effect to also study an alternative site, based on the principle that alternatives should be considered before the nation embarks on large financial commitments. A better alternative site for a large reservoir had been identified upstream of Lunuganvehera, at Huratgamuva, immediately below the confluence of the Kuda oya and Kirindi oya. When engineers in the Ministry of Planning informed the new Minister about the need to study the alternative site before deciding on construction of Lunuganvehera, he appointed, a Committee of five engineers to report to him on the matter. That Committee, by a majority of three against two, recommended that the Lunuganvehera project should be implemented without investigating the alternative Huratgamuva site, to save time. Minister Dissanayake accepted this recommendation, as he said later, following a dictum of Napoleon that a general could afford to lose a battle, or even a war, but not to lose time. Today, no engineer or layperson can justify ill- fated Lunuganvehera as against Huratgamuva. Instead, diversion of Menik ganga has been proposed to augment Lunuganvehera - a remedy worse than the disease.
Water Resources Development Plan, 1959
Lunuganvehera was selected for investigation from a map called the Water Resources Development Plan, 1959, from which Uda Walawe reservoir had been selected earlier. This map hangs in the office of every important decision-maker in Sri Lanka, from the President of Sri Lanka. to the engineers in the Irrigation department. In preparing this map, the ancient irrigation systems were ignored, with the exception of the very large ancient reservoirs and channels (called yoda ela), like Kalaweva and its Jayaganga, the prima donna of the inter-related groups of large tanks and channels in the ancient Rajarata. These had been mapped and brilliantly described by R L Brohier in his landmark paper to the Royal Asiatic Society in 1935, published in the Journal of the RAS in 1937. The raison d’etre for engineers ignoring the small tanks and anicuts, called ancient minor irrigation systems, was that they considered them to be inefficient. Ergo, small tanks should be replaced by large reservoirs that would submerge groups of them. Thus, literally hundreds of ancient small village tanks lie submerged under the waterspreads of Uda Walawe and Lunuganvehera, that had once been the basis of a flourishing civilization in ancient Ruhuna. The historical chronicle Culavamsa refers to Dvadahassaka desa and Aththasahassaka rata, the regions of eight thousand villages and twelve thousand villages, respectively, obviously the reference being to tank villages. To this day, even though the vast majority of the ancient small tanks in the dry zone have long been abandoned in the face of the cruel jungle tide, the name of a village is often synonymous with that of a village tank.
Recently, when the project for Augmentation of Malala oya basin from Mau ara, a left bank tributary of the Walawe ganga, was taken up, it was found that what were described as "abandoned small tanks" on the topographical survey sheets were not small tanks at all. They were earth embankments not equipped with sluices, described by local people as a vetiya, a term not usually familiar to engineers, although there is said to be an old village by that name in the vicinity. The Irrgation department’s Director of the Mau ara diversion project has decided that these vetiyas should be restored to maintain the water table, and this will also help restore the dry zone forest garden. If this is accepted as policy, it will amount to a tremendous change of heart for traditional irrigation engineers, many of who still argue, from a hydraulic engineering perspective, that small tanks are inefficient. The alternative view of these small village tanks, vetiyas and anicuts (amunas), as micro water and soil conservation ecosystems, is gaining credibility today. The contrast between the hydraulic engineering perspective and the ecosystems perspective lies in a fundamental difference in perception of water. To hydraulic engineers water is inanimate and active, whereas to farmers and agro-scientists, including ecologists, water is animate and passive. Table l below shows the consequences of the contrasting perspectives.
Moragahakande reservoir and the NCP canal
Today, in December 2001, the new Minister of Irrigation and Water Management, the dynamic Jayewickrema Perera will soon face a situation similar to that faced by Minister Gamini Dissanayake in 1977. A proposal for construction of a new large reservoir on the Amban ganga, called Moragahakande, selected from the Water Resources Development Plan, 1959, will be put up to him for approval. Once again, technocrats and the bureaucracy will argue that the project should be taken up for implementation without considering any alternatives, to save time. [Although in this case an alternative called the Kalu ganga diversion has been studied by the Central Engineering Consultancy Bureau]. A certain amount of pressure from impatient foreign aid givers will no doubt compound the Minister’s difficulties in making a rational decision, after some 70 million rupees has been expended on preparation of the Moragahakande proposal alone.
The proposal for construction of Moragahakande has always had undertones of ethnicity, which are not usually mentioned, let alone openly debated. The impression in the lay mind is that those who are for the project (the good guys) are anxious to supply water to water deficit areas in the north central province and beyond; while those who are against the proposal (the bad guys) do not want any water to be diverted northwards. In fact, one lay person who knows nothing about water resources development planning, in a reference to the Moragahakande project, with crude and vulgar irony asked rhetorically: "Doesn‘t good Sinhala water go to Tamil areas under the Mahaweli project?" Such ignorant lay persons should not be allowed to confuse issues that must be openly discussed by those who do understand them, and explained to those who do not.
Criticism of the Moragahakande proposal arises from the layout of the new channel that will take off from this proposed new reservoir across the Amban ganga, called the North Central Province canal. The NCP canal is tracted approximately along the central ridge of the country in Rajarata and will therefore have double banking or embankments on both sides of the waterway. Every ancient yoda ela or giant channel in Sri Lanka, took off from a river or from a reservoir at its head end. It was traced on a falling contour, with only one embankment on the downstream side of the channel, and was called a contour channel. Monsoon season rainfall in the upstream catchment area adjacent to the channel, drains into the channel. In this way the supply of water from the river or the reservoir at the head end of the ancient yoda ela is augmented. Kalaweva (reservoir) and Jayaganga yoda ela (contour channel) were described by Brohier as follows:
The Jayaganga, indeed an ingenious memorial of ancient irrigation which was undoubtedly designed to serve as a combined irrigation and water supply channel was not entirely dependent on its feeder reservoir the Kalaweva for the water it carried. The length of bund hetween Kalaweva and Anuradhapura intercepted all the drainage, from the high ground the east which otherwise would have run to waste. Thus the Jayaganga adapted itself to a wide field of irrigation by feeding little village tanks in each subsidiary valley which lay below its bund. Not infrequenty it fed a chain of village tanks down these valleys - the tank lower down receiving the over-flow,from the tank higher up on each chain.
Since the Moragahakande NCP canal will be in double banking, no such interception of local rainfall will be possible. The NCP canal will be just a supply channel like the canals in California that bring water from sources in the north to the south of that longitudinally extensive state. In California, the annual rainfall is extremely low in comparison with the rainfall in the Rajarata in Sri Lanka, and in any event the local topography rarely permits a contour channel. A large ridge channel in double banking is therefore appropriate for California, but is meaningless our Rajarata or elsewhere in the dry zone of Sri Lanka. Another danger of the proposed NCP canal is that there will be theft of water from both sides all along its northerly course from Moragahakande reservoir. Conflict over water will add an east-west dimension to the existing north-south ethnic conflict. And, unlike the north-south conflict, which may be amenable to a negotiated settlement soon, the east-west conflict will be with us forever. Further, the scale of theft of water from the NCP canal will inexorably increase with time, with little chance of any peaceful settlement. Incidentally, the question may be asked whether there is no theft of water in California? There certainly is and there is no need for us to emulate them, particularly as it is on a grand scale of duplicity as documented in the classic study Cadillac Desert by Marc Reissner.
A River for Jaffna
Instead of Moragahakande, a project that was once under consideration in the Irrigation Department should be taken up. This is called the Arumugam Plan or A River for Jaffna due to the late S Arumugam, former Deputy Director of Irrigation during the Golden Era of that department, (so described in the Irrigation Centenary volume, 2000), who passed away in London, last year at the age of 95 years. The plan envisages conserving in the Elephant Pass lagoon, flood runoff from Iranamadu reservoir which spills into the Kanagarayan aru, from time to time. This lagoon had been isolated from the sea by salt water exclusion structures at its eastern and western ends, (which however are now in a state of disrepair). Over the years, by a process of infinite dilution, the lagoon would be converted to a fresh water lake. At a later stage it would be connected to the Vadamarachchi lagoon, which too would eventually become a fresh water lake, and the ground water table in the Jaffna peninsular would be considerably enhanced. This had happened when this project was initiated when President J R Jayewardene held office. The new Minister and government would do well to re-open this proposal for technical and public scrutiny. It could be a major step away from the hydraulic engineering of the Water Resources Development Plan, and a long overdue step towards a more sustainable and stable Water and Soil Conservation Ecosystems policy in water resources development planning.
Water and Soil Conservation Ecosystems
The so-called ancient irrigation systems of Sri Lanka, still considered a wonder of the world, should be seen as water and soil conservation ecosystems, and treated as part of our cultural and economic heritage. The savant Judge C G Weeramantry, former Vice President of the International Court of Justice, brought this to the attention of the western world in a famous Separate Opinion in the Gabcikovo - Nagymaros case (the Danube dam case) that is much cited in the field of environmental law today. Dr Weeramantry said that all 15 judges of the World Court had visited the Danube dam site, and other judges had been visibly impressed by the size of the reservoir. When Dr Weeramantry told them that there were even larger reservoirs in his country, Sri Lanka, some of which had been built two thousand years ago in pre-Christian times, the learned judges had admitted that they knew absolutely nothing about them! That was the reason for Dr Weeramantry’s well researched, scholarly Separate Opinion, which has been republished locally for the Institution of Engineers, Sri Lanka, and should be mandatory reading.
In this context, it must also be mentioned that many of our engineers, like the learned Judges of the World Court, know little or nothing of the ancient water and soil conservation ecosystems of Sri Lanka. This is revealed from time to time, sometimes in embarrassing circumstances. For example, in September 2001, the Institution of Engineers organized a seminar on River Basin Management, at which the Resource Persons were two foreign engineers, one from the Snowy Mountains Authority in Australia, the other from the International Water Management Institute (IWMI) in Colombo. During a full day’s discussion no one mentioned the ancient irrigation systems of Sri Lanka, where river basin management had been practiced on a far more complex scale than even in the accelerated Mahaweli project, as documented in the Concise History of Ceylon by Paranavitana and Nicholas. (Reference was made to the Tennessee Valley Authority without mentioning that this grandiose project is now considered a failure). Towards the end of the conference I mentioned that R. L. Brohier’s classic Ancient Irrigation Works in Ceylon, published in 1933-34, and S. Arumugam’s Water Resources of Ceylon published in 1969, give all the information needed for a study of the ancient systems in Sri Lanka. In answer to a question by me the IWMI resource person, (who in professional terms is a friend of mine) said that he had not even heard of Arumugam’s work! Sadly, I had to say that he was being misled by his counterpart Lankan engineers, a case of the blind leading the blind.
To sum up in conclusion:
• The new Minister or Irrigation and Water Management should not be stampeded into approving construction of the Moragahakande reservoir and the NCP canal, as the then new Irrigation Minister was maneuvered by the bureaucracy and technocracy into approving construction of the Lunuganvehera reservoir project in 1977, which is now recognized as a colossal failure. (Incidentally, the Huratgamuva alternative may have to be taken up soon).
• The proposal called a River for Jaffna or the Arumugam Plan should be taken up for study and implementation without delay.
• All engineers in the Ministry of Irrigation and Water Management should be put through a crash course on the ancient irrigation systems, which should be recognized as water and soil conservation ecosystems. These systems that have been treated as a liability, should instead be treated as an economic asset, because they embody all the important features of modern environmental conservation theory, only now being discovered and developed in the west.
• The problems in the southern area, specially in the Lunuganvehera and Uda Walawe project areas, should be studied from an ecosystems perspective, with a view to finding stable and sustainable solutions to the environmental degradation and consequent socio-economic problems in the area. These problems have contributed to two attempted insurrections in the country. Lessons from ancient water and soil conservation ecosystems in the southern area and elsewhere if properly learned and adopted will offer lasting solutions to these problems.
Hydraulic Engineering vs. Water and Soil Conservation Ecosystems
Hydraulic engineering Ecosystems perspective
perspective - (Soft technology)
1.Water inanimate, active animate, passive
2.Small tanks inefficient, early stage in micro water and soil evolution and development, conservation ecosystems to be submerged by large essential component of macro reservoir built later water and soil conservation ecosystems
3.Large reservoir efficient system in main item in macro water combination with channel and soil conservation eco-distribution irrigation system, with micro water system and soil conservation eco systems in command area
4.Diversion channel built to augment large earliest stage in irrigated reservoir — last stage in agriculture and evolution development of irrigated and development of water agriculture system and soil conservation ecosystems
5.Vetiya abandoned small tank deflection structure -micro water and soil conservation ecosystem; maintains water table
6.Downstream development area cleared of all vegetatiopn to must be designed as a lay out channel irrigation series of micro water and system soil conservation ecosystems, including forest areas
7.Forest areas limited to catchment areas not only in catchment areas - should be interspersed with fields in development areas for better nutrient flows
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