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Save Parakrama Samudraya!



By Bandula Kendaragama, Dam Safety Consultant, Melbourne, Australia

This article is written based on information collated through consultations that were submitted as a technical report recently to President Gotabaya Rajapaksa and other relevant government authorities. The consultations were among those who had been interested in dam safety and directly involved in managing the “Narrowly-Missed” breach and in the reconstruction of the Parakrama Samudraya bund after the Cyclone in 1978. They considered it appropriate in sharing concerns and acquired knowledge with the public at this crucial juncture of decision-making on the safety of the aging irrigation infrastructures in Sri Lanka.

The Parakrama Samudraya Reservoir was built by King Parakramabahu the Great, during his reign (1153-1186 AD) and it has a reservoir capacity of 116,000 acre-feet, feeding approximately 25,000 acres of paddy cultivation. This reservoir has a bund 52 feet high and 10 miles long.

The study on the Parakrama Samudraya bund was undertaken owing to information and misinformation that had been widely shared and debated in the formal media, and especially in the social media, concerning the Parakrama Samudraya bund being proposed as a site to construct an 8-feet wide walking path. Further, it is noted that similar walking paths will be constructed on bunds of other reservoirs such as Kantale, Udukirala Wewa, etc.,

Cyclone in 1978

The 1978 Cyclone started with the onset of the storm formed on 20 November 1978 over the southwest Bay of Bengal. It intensified gradually, reaching Super Cyclonic Storm Status Category 4 Cyclone on 23 November with a gusty wind speed of 220 kmph. The 1978 Cyclone was the second strongest Super Cyclonic Storm to strike Sri Lanka’s Eastern Province since modern records began. The cyclone attained peak intensity on November 23, before making landfall in Batticaloa. The Eastern Province was heavily affected by the cyclone.

The cyclone had devastating impacts in Sri Lanka, killing about 915 people and an unaccounted number of cattle and other animals. An estimated more than one million people were affected, with over 250,000 buildings damaged, and one-fifth of Batticaloa’s fishing fleet destroyed. Nine of the 11 paddy stores were destroyed and 90 % of the coconut plantation (about 28,000 acres) in the Batticaloa district were destroyed. Also, in Polonnaruwa District, the public and private infrastructure, paddy, and rice stored in Food Commissioners and Cooperatives, coconut cultivation, etc., were devastated.

Cyclone 1978 and Parakrama Samudraya

The Cyclone reached the Parakrama Samudraya bund at about 6:30 pm on 23 November and lasted till about 4:00 am on 24 November. According to eyewitnesses, the height of the waves was 10 to 12 feet. Knowing the imminent catastrophic danger of overtopping leading to a breach of the bund, the Irrigation Engineer in charge of Polonnaruwa A. D. S. Gunawardana, the Government Agent Polonnaruwa Austin Fernando, and a few other officials, on duty, decided to be ready with a few bulldozers and retain them standby at strategic locations such as at the sluice and spillway, to breach the bund at these locations if the need arises.

The idea behind this decision was if the predicted overnight rainfall occurred and the anticipated inflow to the Parakrama Samudraya did really eventuate, the inflow would have been greater than the outflow with all 10 radial gates and the sluice gates kept open. Then there was a risk of overtopping and breaching the bund. Hence, an artificially introduced breach of the bund to discharge floods along the existing channels would prevent a haphazard catastrophic breach at an unknown and unwanted location, which could inundate the heavily populated downstream areas. Such an emergency rapid drawdown is the standard practice to prevent a dam breach. Fortunately, predicted overnight rainfall was low. However, the drawdown of the reservoir continued overnight.

Following the overnight drawdown, about 2/3 of the 12-feet wide bund top road and a fair portion of the upstream shoulder were found to be slipped into the reservoir, leaving only about 1/3 of the bund top road intact. There were widespread such slips along the full length of the bund. The damaged areas were repaired with earthfill and Ralapanawa reinstated as a short-term risk reduction measure. The upstream face of the Ralapanawa was not flattened to improve the safety margin (i.e., Factor of Safety) of the bund in case of future similar drawdowns as it was a long-term risk reduction measure to be implemented by the Government Authorities. Therefore, consideration should be given to implementing appropriate long-term risk reduction measures.

Walking Track Proposal

Based on information available to date, the proposed walking path will be constructed on the upstream side of the bitumen surfaced bund top road where there was a sliding failure during the 1978 cyclone and floods (See Figure above 1).

Several long tension cracks, sealed with tar, are present on the bitumen surfaced bund top road as seen in videos of Sri Lanka media. Most of them are located along (parallel) the bund top road, thus increasing the risk of sliding failures similar to those that occurred during the 1978 floods. Additional loads due to the construction of a walking path would widen and deepen those tension cracks, compromising the safety of the bund, which is not known.

Therefore, it is the considered view that additional loading on top of the 1978 sliding mass for construction of the walking path would increase the risk of reactivating the 1978 slides during a future rapid drawdown, similar to in 1978.

It is understood and appreciated that the Irrigation Department is currently undertaking geotechnical investigations to assess the safety margin of the bund.

The highest concern is dam-safety

Based on information available, it is understood that there is a period of 741-years (i.e., from 1159 to 1900), where the performance of the bund is not documented and unknown. However, it is reported that the bund was totally breached during the colonial era. According to R L Brohier, the bund and the reservoir were abandoned for more than a century.

Given that the population at risk in case of a dam break is extremely high, it appears that the consequence category of this bund is “Extreme” as per the current international dam safety guidelines. Therefore, the proposed walking path at Parakrama Samudraya cannot be compared to that of the Kurunegala Wewa, Boralesgamuwa Lake, etc., constructed along the reservoir rim, and the walking paths constructed around water bodies in the suburbs of Colombo.

It is understood that the Parakrama Samudraya is formed by combining three reservoirs of unknown history. Therefore, the bund may have been raised in several stages during the 741-years associated with unknown performance. It is not known whether dam safety-related defects of the bund such as slips or slides, cracks, animal burrows, sinkholes, soft areas, root bowls, zones of desiccation cracking, zones of residual shear strength because of historical failures, etc., were repaired to satisfactory standards, or not.

The aging of dams constructed of earth and rockfill material is due to time-related changes in the properties of the materials of the structure and its foundation. As reported in a technical paper published in May 2010 by the United States Society of Dams, the aging or deterioration of embankment dams and their foundations are of concern. These concerns extend throughout the entire life of the dam until safe abandonment or demolition.

Recent interventions on dam-safety

Given the dam safety issues associated with this controversial walking path project, the Water Forum of the Institute of Engineers in Sri Lanka conducted a Webinar on 09 September 2021 on “Usage of Inland Water Bodies for Recreation”. More than 280 personnel, mainly engineers, participated in this Webinar and raised over 100 questions related to the safety of the bund. Several questions were raised on fundamental errors and potential failure modes associated with the proposed walking path. It appears that ad hoc decisions have been taken for reasons unknown. The lack of laws and dam safety regulations in Sri Lanka could be one of the reasons for such ad hoc decisions taken by various individuals and organisations.

As far as dam safety regulations are concerned, India is well ahead of Sri Lanka. Even Ghana in Africa has introduced Dam Safety Regulations to ensure the safe design, construction, operation, and maintenance as well as decommissioning of dams.

Based on statistics of embankment dam failures and accidents, 48% of dam failures are related to overtopping and failures of appurtenant structures, and 46.5% are due to internal erosion. Due to the absence of an internal filter system in this bund, not only the slope instability, but the internal erosion is also likely to be a prominent potential failure mode.

It is understood that planning is underway to construct several fast-food outlets, toilet facilities (including a “changing room”) at the toe of the bund, i.e., within the reservation area of the bund located immediately downstream of it. It is to be stressed that this stretch of land along the bund is a critical area to ensure the safety of the bund. Identification of dam safety features such as heaving the ground, cracks, wet areas, springs, seepage locations, etc., in this area, is critical. Digging of lavatory pits, trenches, etc., could intercept permeable layers in the foundation and may trigger “backward erosion tunnels” leading to piping, which is a major failure mode in embankment dams (or, bunds). Excavations in this area could lead to sides of the downstream face of the bund, compromising its safety margin.

Should there be a need to improve the safety margin of the bund, additional stabilizing fills are to be constructed in this area over the downstream face of the existing bund. An access road along the downstream toe of the bund is an essential item for repairs and routine maintenance of the bund. Given the proximity to the dam, this reservation area should be used to stockpile materials to be used during dam emergencies such as filter sand, crushed rock, rockfill, etc., and movement of construction machinery for maintenance and repairs. This area is an integral part of the bund, hence should not be used for either permanent or temporary constructions. Therefore, consideration should be given to providing these facilities at an alternate suitable location, perhaps close to the Government Agent’s residence, or thereabouts.

Recommendations to maintain dam safety

Based on dam safety concerns and consequences discussed, it is recommended that,

1) the crest of the bund is reserved for routine maintenance, including replacement of displaced Ralapanawa if necessary, placement of additional boulders if required, and for construction of temporary overtopping protection bund using ‘Sandbags”, as and when required.

2) the stretch between the Ralapanawa and bitumen road be reserved for the construction of a wave wall to meet the dam safety requirements of future hydrological reviews to be undertaken during the service life of the reservoir and bund.

3) a safe “Load Capacity” be imposed on the bund top road, and arrangements are made to stop all heavy trucks plying on the bund top road as the bund has not been designed for such traffic loads.

4) the bund top road is completely closed for all traffic, say from 5:30 am to 7:30 am and then from 6:00 pm to 9:00 pm or as agreed by local authorities, in the preferred 2km long stretch, and then the existing bitumen surfaced bund top road to be used as the walking path (Alternatively, only the upstream-half of the bitumen surfaced bund top road to be used as the walking path while the downstream-half of the bitumen surfaced bund top road to be kept open for one-way light traffic only, subject to nominated maximum speed to ensure the safety of people using the walking path).

5) an alternative walking path (For example, in the reservoir rim), be investigated which will not compromise the safety of the dam.

6) the reservation area located immediately downstream of the bund is not used for developments that are been planned by the Urban Development Authority as this area is very sensitive to dam safety issues.

7) the reservation area located immediately downstream of the bund, which is an integral component of the dam, be a property of the Irrigation Department for inspection and monitoring of critical dam safety features, construction of a toe access road, construction of stabilizing fills if required, stockpiling of construction materials required during dam emergencies, etc.,

8) a potential failure modes analysis and Risk Assessment be undertaken in accordance with international dam safety standards.

9) a Design and Safety Review of the dam and appurtenant structures be undertaken in accordance with the international dam safety standards incorporating review of geotechnical parameters of the bund and foundation, hydrology, wave run-up, seismicity, flood handling capacity, reliability of gates and instrumentation, etc.,

10) sufficient funds must be allocated to undertake Design and Safety Reviews of all “Extreme” consequence category dams in Sri Lanka.

11) sufficient funds must be allocated to routine maintenance of dams (Note: Depending on their nature, some maintenance items, if not addressed in a systematic and timely manner, may eventually become dam safety issues, eventually leading to failure of dams).

12) early arrangements must be made to implement the recommendations of the Cabinet Memorandum No. 11-2020 dated 26 October 2020 on the Establishment of a Dam Safety Consultation Centre and a Dam Safety Regulatory Mechanism.

(The author can be contacted on email:

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Artificial intelligence and reality of life



by Dr D. Chandraratna

Ever since President Ranil Wickremesinghe announced his desire to use Artificial intelligence (AI) to develop all sectors, from banking to agriculture, in Sri Lanka several correspondents have enthusiastically endorsed those sentiments in the print media. There is no gainsaying that technology has already made huge inroads into our lives, the latest paradigm adopted and articulated by the developed countries is thrust upon all mankind as the harbinger of a beautiful new world. Just as in an earlier time when the liberative potential of science created an understandable anguish about its misuse, similar forebodings are felt about the future curated by the super machines. Though unlike in the earlier debates where the misuse was calculated in terms of unlikely human catastrophes the current anguish is more about its ever -present transformative potential of the human world.

Most of the developed countries in the Western world, and Australia have launched statutory guidelines in the ethical use of AI. The Chat GPT, it has been cautioned in some quarters, poses such a risk to humanity that it must be subject to stringent regulation as nuclear power. Open AI founder Sam Altman has said that within a decade AI system would be capable of exceeding human expert skill levels in every domain. Given its possibility to be powerful than all other technologies experts predict that AI poses an existential risk like nuclear energy and synthetic biology. Silicon Valley experts are talking the need for a global regulatory body like the international Atomic Energy Agency (IAEA).

In the field of education, it risks accuracy and reliability of knowledge, the sources of information, academic integrity, student learning capabilities ending up with a humanity’s self-perception. Six months after Open AI launched ChatGPT, Australian University teachers have stated that they are unable to prove students who cheat with AI because still there is no regulatory body. At a conference held in Sydney last week Senior academics have railed against AI as ‘a tool in education’ because of ethical concerns, built in biases, fake knowledge and hate speech. AI is also generating enormous wealth through education in the hands of a few white male billionaires who are living off surplus value created mostly by brown and black workers.

One Deakin University academic has said it is only a data exchange service and an academic from Macquarie University said that ChatGPT app could easily be used by weak students to obtain enough marks to pass examination. Teachers may have to use open assessments and other examination methods to evaluate students. Students may be tempted to undermine their own desire to acquire knowledge in preference to the attraction of credentials to further their career prospects. Given the fact there is in the developed world a phenomenon of ‘degree inflation’ the quality and value of higher education will diminish. If cheating with the help of AI increases one’s chances of gaining the credentials thereby reducing the lure of understanding many students will not scruple to do so.

It is also the case that AI has the potential to make many employment opportunities ‘surplus to requirements’ in the knowledge economy for AI is efficient and cost cutting. Data analytic employment in multiple industry sectors will vanish overnight. Because of the fears of ChatGPT share prices of many education organisations have plummeted overnight. With the announcement of the ChatGPT, US company Chegg, which produces homework study guides, lost heavily on the stock market with more than half its workforce facing retrenchment.

There are other dangers. The value of education as character building, knowing yourself, examining one’s life, becoming wise, which are the wider objectives of education lose their appeal. Education is reduced to a process of credentialising to make us employable. AI is driven by a few mega corporations whose commercial motives are not aligned with the wider purposes of education beyond the why and the how. Education in the AI era will be concentrating on skills for employability. It can change the current paradigm of education. AI has the potential to cultivate a narcissistic and misguided anti-intellectualism which can shut out reasoned debate on public issues.

This existential threat to our sense of personal autonomy and human agency cannot be ignored. We must legislate to protect those aspects of humanity that are exclusively human and vitally important to the functioning of democratic communities. We should be alert to the fact that AI cannot replace nuance. It is soulless, cannot feel pain or loss, has no heart and no intuition. AI like all replacements to the original will disappoint us at the crucial hour for it cannot replace years of experience, innate ability, and intuitive wisdom.

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Palm oil growers await green light for sustainable production



A young oil palm plantation having a thick legume cover crop

By Emeritus Prof. Asoka Nugawela

Palm oil is a versatile commodity. It is used in numerous products world over. The global usage in 2022/23 is estimated as 76 million metric tons. Accordingly, the average global per capita usage is in the range of 10 kg per annum. Sri Lanka too recorded similar usage during 2018/2019 period, prior to economic downturn in the country. Palm oil usage is very much higher than the usage of other vegetable oils such as coconut, soya, canola, sunflower, rape seed and olive. One major reason for the relatively high per capita usage of palm oil is the affordability to purchase and its availability. Per unit land area, the oil production is four times greater in oil palm when compared with coconut. When comparing with other crops grown for vegetable oil production it is about tenfold higher. Further, oil palm, coconut and olive are perennial crops whereas soya, sunflower, canola and rape seed are short term crops. With short term crops the capital cost component is relatively high with yearly land clearing, land preparation and planting activities to be undertaken. Oil palm with a high oil yield and having a 30-year economic life cycle has the ability to provide a relatively cheaper vegetable oil than from other crops. With perennial crops the disturbance to the soil properties and biodiversity is less than in annuals and is a positive attribute as far as sustainability is concerned.

One other reason for palm oil to be the preferred vegetable oil is because it contains both saturated and unsaturated fatty acids in almost equal proportions. Thus, it is different from coconut and other vegetable oils which contain a relatively high percentage of unsaturated fatty acids, around 90%. Palm oil with its 1:1 balance of saturated and unsaturated fatty acids is the preferred choice for many applications in the food industry.

Both the type and the number of fatty acids of fat in our diets are known to influence health and wellbeing. The present global advice is to increase the consumption of unsaturated fatty acids at the expense of saturated oils and fats. For optimal health we require a mixture of fatty acids to be present in our diet. In this context among the sources of dietary oils and fats palm oil could be viewed as a relatively better option for its ‘mixed’ fatty acid profile (saturated, mono and polyunsaturated fatty acids).

The relative advantage in the return on investment the oil palm crop is having over other plantations crops also drives the investments towards this crop. This is true for both plantation and smallholder sectors in major palm oil producing countries in the world. The profitability from different plantation crops grown in Sri Lanka under average management conditions and current agrochemical/material costs & trading conditions are summarised in Table 1. Accordingly, oil palm is by far the most profitable plantation crop in the country. (See table)

The country has a demand for palm oil as a cooking oil and also as a raw material for many other industries. The products made in these industries are essential and widely used. For vigorous growth and high yields oil palm crop should ideally be grown under tropical climatic conditions with more than 2,500 mm of rainfall per annum. The low country wet zone of the country is blessed with such climatic conditions. The return on investment is high with this crop. However, even under such a favorable business environment for this industry, the government of Sri Lanka has taken a decision to ban cultivating this crop in the country. All other palm oil producing countries in the world, i.e., more than 20, are surprised and view this as a wrong decision.

Some repercussions of this decision to ban oil palm cultivation in Sri Lanka are a). dependency on other countries to fulfill our vegetable oil need, b). loss of foreign exchange to the country by importing palm oil, c). loss of income to the potential investors, d). loss of employment opportunities and e). depriving potential smallholders, the opportunity to enhance their livelihood. Prior to the economic crisis in this country, around 200,000 MT of crude palm oil (CPO) had been imported annually. The current global market price of a metric ton of crude palm oil is around 900 US$. Thus, the foreign exchange requirement to import national crude palm oil requirement will be more than 180 million US$ per annum without freight and insurance costs.

In the past, forests have been felled to cultivate oil palm in some major palm oil producing countries. The same approach was adopted for planting other plantation crops as well in the past. Deforestation will invariably lead to further shrinking of already depleted forest cover and loss of environmental services we accrue from natural forests. Natural forests significantly contribute to depleting of greenhouses gases, to the natural water cycle and protects biodiversity, soil, catchment areas, rivers and water bodies. Due to serious negative impacts of deforestation on the environment, a worldwide lobby demanding countries to grow oil palm in a more sustainable manner was initiated. With this lobby changes are now taking place in the manner in which land is selected to grow oil palm. For most crops including oil palm, systems to certify sustainable plantation management have evolved and such certification has become a requirement for marketing of produce from plantations. Basically, issues related to cultivating oil palm had been identified, awareness created amongst parties concerned and interventions for rectification have been put in place. In Sri Lanka however, to start with there was no issue of deforestation associated with oil palm cultivation. The land for cultivating oil palm in Sri Lanka was obtained through crop diversification, a scientifically accepted approach. Even then cultivating of oil palm in Sri Lanka was suddenly banned by the government incurring the investors a loss of more than Rs. 500 million on nursery plants alone. The global lobby was against felling forests to plant oil palm. The reasons for the anti-oil palm lobby in Sri Lanka according to some environmentalists, scientists and politicians are negative impacts to the environment, loss of biodiversity, depleting soil water and threat to the existence of other plantation crops. There is no scientific basis for such allegations. But those who lobby against planting oil palm do not want to understand the difference between ecological impacts when planting oil palm subsequent to felling natural forest cover and as a crop diversification program. Various attempts made had been futile and as the Sinhala saying goes it’s like trying to wake up a person who pretends to be sleeping.

The necessity for a country to produce its own needs is more than evident now with the economic crisis the country is facing currently. With a huge disparity in outflow and inflow of foreign exchange to the country the need to produce our own requirements are very much obvious. As explained earlier in this article Sri Lanka has a conducive business environment for a successful palm oil industry. What is lacking to drive the industry forward in the country is the political will. Politicians may be fearing that a decision to lift the ban on oil palm cultivation will not be a popular decision affecting their vote base. Countries economy is currently shrinking leading significant losses in employment, falling income levels, increased inequality and government borrowings. To recover from such an economic crisis the country should not ignore viable industries that could enhance national production. A reversal to the decision to ban oil palm cultivation will lead to producing national requirement preventing the outflow of millions of dollars each year. Revenue moving out will circulate among all stakeholders of the industry helping to enhance their livelihood and strengthening the economy of the country.

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‘Modabhimanaya’ everywhere



The events relating to the recent arrest of a ‘stand-up comedian’ who is allegedly to have insulted the Buddha and Buddhism can be taken as a true reflection of how confused the Sri Lankan society is when it comes to the adoption of religion and law-and-order in their true meaning.

There is absolutely no argument about the sheer folly and callousness on the part of this person in picking such sensitive material as part of her comedy gig. There can be arguments as to whether it was intended to be as derogatory to the Buddha as it seemed on the face of it when the context and the content of that gig are considered in total. But that is completely beside the point. Even if the intention wasn’t malicious, it was a grossly stupid (moda) and improper choice for which proportionate consequences must be expected.

However, have we done any better as a society in the manner we have chosen to react to this event from either a Buddhist or a law-and-order perspective? Apart from a few sane words by a minority, what we could mostly see is an equal measure of idiocy, laced with confusion, hypocrisy, inconsistency, and hatred. The immediate reaction of some of the so-called protectors of the Buddha Sasana seems the complete opposite of the fundamental teachings expounded by the Buddha in his great wisdom. Reacting in this manner begs the question as to what exactly they’re trying to protect and from whom.

Whenever the Buddha was challenged or insulted, which seemed to have happened occasionally during his lifetime, he never encouraged his followers to lose their minds or to seek revenge. The Buddha didn’t rush to enter any defamation complaint at the royal courts either. He only did his best to make his accusers understand and see the truth for themselves. That was done with complete kindness – not with a revengeful heart.

Buddha’s teachings are so profound that his followers are supposed to become wise, stable, and strong enough to be able to handle any praise or contempt that come their way without losing their own minds. It’s therefore very unfortunate (and amusing) to see some of the “followers and protectors” of the Buddha’s teachings, including some Monks, grossly deviate from the teachings they themselves claim to follow and protect!

The law-and-order perspective in this regard also seems to lack clarity and consistency like in many other similar areas. While the provisions of ICCPR Convention were extremely progressive and well-intended, the way our local ICCPR Act is being used leaves a lot of questions than answers.

There appears to be some confusion or misunderstanding about the true intentions of this Act and under what circumstances its provisions should be used. To prevent any misinterpretation or misuse, the ICCPR Convention had clearly emphasised the need for considering the factors like the context, content, intention, potential for violent reaction, etc. before making a call. In the absence of such consistent guidelines, our ICCPR Act could easily become putty in the hands of our scheming politicians and their lackeys in the law enforcement machinery.

Haven’t we already witnessed a lack of consistency in this regard in recent times?

Upul P, Auckland

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