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Solution to water deficit in NWP and NCP




Former Section Engineer (Dam), Kothmale Hydro-Power Project and International Dams Consultant, Melbourne, Australia

(Based on an interview with Srilal D. Perera (Construction Project Manager), Melbourne, Australia)

Sri Lanka is now a middle-income country with consistently high economic growth over the recent years. The government’s public investment plans include several development plans and projects for the coming years, to further accelerate economic growth and promote social and human development.

Being a tropical island located close to the equator, Sri Lanka is highly susceptible to adverse effects of climate change. The Global Climate Risk Index (CRI) 2018, which indicates how countries have been affected by the impacts of weather-related loss events (storms, floods, earthquakes, heat waves etc.,) ranks Sri Lanka as the fourth among the most affected countries of the world. This is an alarming situation. Adverse effects of climate change are evident from the severe and long duration droughts as well as severe flooding occurring almost every year in several parts of the country. Water availability is becoming more variable and uncertain, even as demand for bulk water supplies for agriculture, new industries and tourism and clean water for drinking increases. Studies confirm that these impacts are likely to exacerbate, and the wetter areas of the country would eventually become wetter, and the drier areas drier and drier.

The government of Sri Lanka has taken steps to address these challenges with the successful completion and commissioning of Moragahakanda and Kalu Ganga reservoirs, and the ongoing and planned construction of dams and associated feeder canals, hydraulic facilities, Hydro Power enhancements to comply with Paris Convention that His Excellency the President of Sri Lanka has consented under renewable energy promotion in Sri Lanka; as well as, other water resources development investments envisaged under the Public Investment Plan (PIP). The Government is also implementing several other programs and investments to mitigate flooding and flood damages in several river basins which are vulnerable to flooding.

Planning and investments in additional water storages, and transfer infrastructure to transfer water from water surplus river basins of the wet zone to water deficit river basins, will be a major priority to meet the growing demands and challenges of climate change impacts. Additional investments will be required on a priority basis for developing water resources to provide potable water supplies to people and areas currently affected by chronic kidney disease.

These new investments on water resources will demand diligent planning, protection, management and allocation of water for multiple uses and users within river basin context. As the water infrastructure expands through additional infrastructure bringing water to water deficit geographic areas, to new and current groups of farmers, large and small industries, urban and rural drinking water consumers, mechanisms will be required for diligent planning, allocation, and monitoring of bulk water supplies from the major water conveyance systems beyond the mandate and the role played by the existing Water Management Secretariat (WMS) of the Mahaweli Authority of Sri Lanka (MASL).


The Project

With the present climatic uncertainty, North Western Province (NWP) and the North Central Province (NCP) are among the most affected areas without reliable supply of water for irrigation, about 40,000 ha, and ensuring domestic water supply to families in such provinces. Major diversions of this water are supplied through the Polgolla tunnel (875 Million Cubic Meters (MCM) / Year) for both the seasons of Yala and Maha. This volume of diversion is entirely depending on the storage above the Polgolla barrage. At present only the Kotmale reservoir with 174 MCM supports to regulate this water. However, the Polgolla tunnel is functioned only with 60% of its capacity, and the tunnel has additional capacity to divert around 400 MCM / Year, if the upstream storage is available.

Therefore, a proposal for increasing the height of the Kotmale dam to increase the retention capacity by additional 250 MCM would be one of the feasible proposals to solve the water deficits in NWP and NCP. Also, the increased head and volume would boost the hydro-power generation by about 20%, once the supplementary water starts to pass through Kotmale and Ukuwela power stations.

The Kotmale Hydropower Project was one of the first projects taken up under the Accelerated Mahaweli Development Program (AMDP). It was the most upstream among those headworks in the Mahaweli river basin, and exploited the hydropower potential of Kotmale Oya, a major right bank tributary of the Mahaweli Ganga. The Kotmale dam site is at Kadadora, located about 6.6km upstream of the confluence of Kotmale Oya with Mahaweli Ganga, where the river forms a narrow and deep valley with steep banks. The powerhouse is underground and situated in the belly of the Atabage mountains, about 6.4km downstream of the Kotmale Oya – Mahaweli Ganga confluence.

The basic elements of the Kotmale Hydro-Power Project are a concrete face rockfill dam (87m high and 600m long) having the active storage capacity of 174 MCM and a tunnel system leading to 201MW power plants with outfall to the Mahaweli Ganga. The primary function is the generation of electric power. Additional benefits arise from an increase in the amount of irrigation water available at the Polgolla diversion, as well as mitigation of floods in the Gampola area as a result of the regulation of flows in the Kotmale Oya. The Project construction work commenced in 1979 and was completed in 1985, with financial assistance provided by the Government of Sweden.

The dam has been provided with basic facilities for future rising, to three alternative levels 715m, 725m and to 735m above the sea level (capacity of 370 MCM at 728m FSL). The provision for the extension of foundation from the downstream face, and the land around the reservoir rim up to 735 m elevation, have already been acquired since the beginning to enable the future upgrading.

However, the raising of Kotmale dam would be an engineering challenge and need in depth study to check the stability of the Concrete Face Rockfill Dam (CFRD), during and after construction, instrumentation, reliability of foundation and geology, supplementary grout curtain, spill gates and chute with elevated ogee (Flip bucket), added pressure head to tunnels, height of the surge shaft and power station equipment etc., Also, the heightening of the dam shall not affect the ongoing annual supply of water to NCP, as it would generate critical social problems and, therefore, the live construction method statement with the active storage of water available for downstream use would be the most practical approach.

Therefore, a comprehensive feasibility study shall be originated to find a solution for the critical water deficit in NWP and NCP, and for harnessing addition of renewable energy, considering above referred to facts at earliest possible.

The original consultant of this project was Sir William Halcrow & Partners (Halcrow Water) of the United Kingdom (UK); and Skanska (Sweden) with joint collaboration of Central Engineering Consultancy Bureau (CECB) , then local Consultant to the Mahaweli Ministry, had been involved in a preliminary feasibility study, the project design and supervisions during the first construction phase of this development in the year 1979 to 1984 period. Hence, the re-engagement of previously involved qualified consultants would be highly recommended for future studies and development, as well as the previous data, knowhow and experience that retained with them would be essential for accomplishing this challenging task.

In addition, consideration should be given to appointing a Panel of Experts from local & overseas professional bodies, who have extensive knowledge and experience in CFRDs, gates and valves, geology, geotechnical engineering, instrumentation and dam safety.

Consideration should be given to employing a minimum number of expatriate engineers and a maximum number of local engineers.



Following studies are needed to execute to enhance the project more feasible to meet the challenges in climate change, and the supply of more renewable hydro-energy, especially from the power plants newly built in Mahaweli Basin from the Kelani water.

1. Raising Kotmale Dam (15, 25, 30m). Note all lands are already acquired and there is no social impact;

2. Check the possibility of building dams at locations 11, 12, 14 etc., in Master Plan above Polgolla near Ginigathhena (Koladeniya, Carolina, Trapalga, Rosalla, to increase the retention above Polgolla, as the water about 1,000 MCM / Year is spilling down Polgolla during flood;

3. Enhance the capacity of Kandalama-Huruluwewa Canal to carry about 200 MCM / Year, at a rate of 10m3/second;

4. Built a new tunnel from Bowatenna Reservoir to Dambulu Oya where the capacity is 30m3/second. This would enhance the deficit of water in NWP (150 MCM / Year) and the water need in Anuradhapura;

5. Expand the capacity of power generation in Ukuwela Powerhouse adding one unit; and

6. Revisit the canal availability from Kalawewa to Nachhaduwa, Tissawewa and Basawakulana etc. via Yoda Ela.

7. A supplementary study to check the availability of water from Kelani Basin to Mahaweli Basin would further enhance this proposal.

The writer has B.Sc. Eng. (Hons), M.Eng. (Structural Engineering & Construction), MASCE, MIE Aust, CPEng NER, APEC Engineer, IntPE(Aus).



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The lasting curse of Janasathu



Kataboola tea estate

Let me begin with two anecdotes.

In the 1960s, my father would pull into the local Shell petrol shed and a smiling pump attendant, smartly attired in a uniform (khaki shirt and shorts) would come up to the driver’s side and inquire what was needed. While petrol was being pumped, the attendant would wipe the windscreen and check the engine oil. The toilet was clean. The air pump worked. To my delight, large, colourful road maps were given out, for free. Sounds like a dream, doesn’t it? All this for about Rs. 1 (one) for a gallon of petrol!

The next anecdote. In 1978, I visited Brian Howie, a former classmate, at Kataboola Estate in Nawalapitiya. Brian was an SD – assistant superintendent – and his bungalow was in a remote corner of the estate, so remote that it had its own mini hydroelectric plant. Mrs. B’s government, which had nationalised the estate, had recently fallen and the estate was now under new management.

The bungalow was sparsely furnished, and I noticed that a corner of the living room was blackened. Brian told me that the previous occupant, a former bus conductor turned “SD”, had not known how to use the kitchen stove, so he put some bricks together and had created a lipa in the living room to do his cooking. Meanwhile, every appliance and item of furniture in the bungalow had been stolen by the same man.

Janasathu has a false ring, meaning “owned by the people”. But, as everyone knows, the term instead means a nest of thieves, running up millions in losses at the cost of the people. A place where friends and political supporters are given employment, showered with generous perks, and given a free run to plunder. Government owned corporations, companies, and “other institutions” run into the hundreds, and perhaps a handful make a profit. The rest are leeches, sucking the blood of the nation.

Do we need a corporation/board for salt, ceramics, timber, cashew, lotteries, fisheries, films, ayurvedic drugs, handicrafts? For a publisher of newspapers? They are so swollen with employees that their raison d’être appears to be employment, perks and plunder that I mentioned above.

I recently read that Sri Lankan Airlines, the CTB, the Petroleum Corporation, and the Ceylon Electricity Board are the biggest loss makers. The Godzillas among them appear to be Sri Lankan Airlines, which reportedly lost Rs. 248 billion in the first four months of this year, and the Petroleum Corporation, which lost Rs. 628 billion in the same period. (The Petroleum Corporations is owed billions of rupees by both Sri Lankan Airlines and the Ceylon Electricity Board.) The Ceylon Electricity Board appears to be a mafia, subverting efforts to promote renewable energy, while promoting commission-earning fossil fuels. While the poorest among our population are starving, the crooks that run these organisations continue to deal and steal.

In Hong Kong, where I lived for 20 years, no airline, bank, petroleum company, telephone service, LPG or electricity supplier is owned by the government. The buses belong to the private sector. In Japan, where I live now, in addition to the list from Hong Kong, even the railways and the post offices are privatised and provide a courteous, efficient service. In Japan, the service at petrol stations is reminiscent of Ceylon’s in the 1960s that I described above.

At least in one instance, Mrs. B attempted to correct her folly in nationalising plantations. The de Mel family owned thriving coconut estates in Melsiripura. After nationalisation, the estates declined to such a sorry state that Mrs. B personally invited the de Mels to take them back. Today, the estates are thriving under efficient management.

As a nation, we need to admit that janasathu has failed, and take steps to remedy the situation ASAP.


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Road to Nandikadal: Twists of Kamal and Ranil actions



I am re-reading retired Major General Kamal Gunaratne’s book “Road to Nandikadal ” these days. This is his first hand experience of the battle against LTTE, and his journey in the Sri Lankan army from Thirunelveli in 1983 to Nandikadal in 2009, where the final battle took place. Thirteen years have passed since the defeat of the LTTE in 2009 under the political leadership of former president Mahinda Rajapakse and the then secretary of defence Gotabaya Rajapakse. As we all know, Gotabaya became the president of Sri Lanka in 2019, and resigned last July, due to public pressure, and is currently travelling from country to country without a set destination.

In his book, Kamal has written an interesting chapter titled “A final chance for peace” and detailed the peace process followed by the then government led by Ranil Wickremesinghe, as the prime minister. This is Kamal’s narrative about the memorandum of understanding (MOU), brokered by the Norwegian government and signed by the then prime minister Ranil Wickremesinghe and LTTE leader Velupillai Prabhakaran in 2002. “According to the MoU, members of the LTTE political wing were allowed to enter government controlled areas to commence their political activities. The first group of such LTTE political wing members entered the government controlled area from Muhamalai, singing and cheering, as if they had won the war. They insulted and jeered at the soldiers manning the checkpoint with impunity whilst the poor soldiers, under strict instructions not to react, helplessly looked on. The Navy, which arrested a group of terrorists, was immediately instructed to release them. Upon release, the terrorists threatened the sailors and lifted their sarongs, baring their genitalia at the stunned sailors, who could do nothing but simply look down in shame. Such developments intensified the apprehension we held of things yet to come and prepared ourselves to face untold humiliation in the name of the Motherland”.

Kamal further writes, “At the time of drafting the MoU, experienced officers like myself, knew it was premature to enter into peace negotiations. On the one hand, LTTE could not be trusted to keep their word, as past experience had taught us bitterly, and on the other hand, negotiations should be ideally undertaken from a position of strength”. He continues, “The government of Prime Minister Ranil Wickremesinghe was very confident of the peace process and strongly believed there would never be a war again. They did not have any confidence in the Army, which spurred this belief and therefore pursued peace at any cost”.

Kamal’s criticism of the Wickremesinghe administration continues: “The step motherly treatment the Army received during this period was terrible. Strict instructions were given to cut costs and the ever obedient army reduced many of our facilities and benefits. The army even stopped the annual issue of face towels to soldiers, given as a benefit for decades. It felt like they wanted us to live like ‘Veddhas’ without a bit of comfort”

Now the same Ranil Wickremesinghe is the President and Commander-in-chief of the armed forces, and Kamal Gunaratne, who was highly critical of the Wickremesinghe administration, is the trusted Defence Secretary of the president. Is it a twist of fate or twist of faith!


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Need for best relations with China



(This letter was sent in before the announcement of the government decision to allow the Chinese survey vessel to dock at Hambantota – Ed.)

I once met Pieter Keuneman sometime after he had lost the Colombo Central at the general election of 1977. We met at the SSC swimming pool, where he had retreated since his favourite haunt at the Otters was under repair. Without the cares of ministerial office and constituency worries he was in a jovial mood, and in the course of a chat in reference to a derogatory remark by one of our leaders about the prime minister of a neighbouring country, he said, “You know, Ananda, we can talk loosely about people in our country, but in international relations care is needed in commenting on other leaders”.

Pieter, the scion of an illustrious Dutch burgher family, the son of Supreme Court judge A. E Keuneman, after winning several prizes at Royal College, went to Cambridge in 1935. There he became a part of the Communist circle, which included the famous spies Anthony Blunt, later keeper of the Queen’s paintings Kim Philby, and Guy Burgess. Eric Hobsbawm, the renowned historian commenting on this circle, wrote of the very handsome Pieter Keuneman from Ceylon who was greatly envied, since he won the affections of the prettiest girl in the university, the Austrian Hedi Stadlen, whom he later married. Representing the Communist Party in parliament from 1947 to 1977, soft-spoken in the manner of an English academic, Pieter belonged to a galaxy of leaders, whose likes we sorely need now.

I was thinking of Pieter’s comments considering the current imbroglio that we have created with China. Our relations with China in the modern era began in 1953, when in the world recession we were unable to sell rubber, and short of foreign exchange to purchase rice for the nation. The Durdley Senanayake government turned to China, with which we had no diplomatic ties. He sent R G Senanayake, the trade minister, to Peking, where he signed the Rice for Rubber Pact, much to the chagrin of the United States, which withdrew economic aid from Ceylon for trading with a Communist nation at the height of the Cold War.

Diplomatic relations with China were established in 1956 by S W R D Bandaranaike, and relations have prospered under different Sri Lankan leaders and governments, without a hint of discord. In fact, in addition to the vast amount of aid given, China has been a source of strength to Sri Lanka during many crises. In 1974, when the rice ration was on the verge of breaking due to lack of supplies, it was China, to which we turned, and who assisted us when they themselves were short of stocks. In the battle against the LTTE, when armaments from other countries dried up, it was China that supported us with arms, armoured vehicles, trucks, ships and aircraft.

It was China and Pakistan that stood by our armed services in this dire crisis. More recently, amidst the furore, created by Western nations about human rights violations, China was at the forefront of nations that defended us. A few weeks ago, it was reported that the UK was ready with documents to present to the UN Security Council to press for war crimes trials against the Sri Lankan military, but the presence of China and Russia with veto powers prevented it from going ahead with its plan.

It is in this context that we have to view the present troubles that have engulfed us.President Ranil Wickremesinghe, in the short period he has been in office, has won the sympathy of people by the speed with which he has brought some degree of normalcy, to what was a fast-disintegrating political environment. On the economic front, his quiet negotiations and decisions are arousing hopes.

A shadow has been cast over these achievements by the refusal to let in the Chinese ship to Hambantota, a decision made on the spur of the moment after first agreeing to allow it entry. The manner in which it was done is a humiliation for China, one administered by a friend. We must remember that these things matter greatly in Asia.

These are matters that can be rectified among friends, if action is taken immediately, recognising that a mistake has been made. The President should send a high-level representative to assure the Chinese leadership that these are aberrations that a small country suffers due to the threats of big powers, to smoothen ruffled feelings, and normalize relations between two old friends. The American-Indian effort to disrupt a 70-year old friendship, will only lead to its further strengthening in the immediate future


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