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Reservoir operation and flooding

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Floods caused by Cyclone Ditwah

Former Director General of Irrigation, G.T. Dharmasena, in an article, titled “Revival of Innovative systems for reservoir operation and flood forecasting” in The Island of 17 December, 2025, starts out by stating:

“Most reservoirs in Sri Lanka are agriculture and hydropower dominated. Reservoir operators are often unwilling to acknowledge the flood detention capability of major reservoirs during the onset of monsoons. Deviating from the traditional priority for food production and hydropower development, it is time to reorient the operational approach of major reservoirs operators under extreme events, where flood control becomes a vital function. While admitting that total elimination of flood impacts is not technically feasible, the impacts can be reduced by efficient operation of reservoirs and effective early warning systems”.

Addressing the question often raised by the public as to “Why is flooding more prominent downstream of reservoirs compared to the period before they were built,” Mr. Dharmasena cites the following instances: “For instance, why do (sic) Magama in Tissamaharama face floods threats after the construction of the massive Kirindi Oya reservoir? Similarly, why does Ambalantota flood after the construction of Udawalawe Reservoir? Furthermore, why is Molkawa, in the Kalutara District area, getting flooded so often after the construction of Kukule reservoir”?

“These situations exist in several other river basins, too. Engineers must, therefore, be mindful of the need to strictly control the operation of the reservoir gates by their field staff. (Since) “The actual field situation can sometimes deviate significantly from the theoretical technology… it is necessary to examine whether gate operators are strictly adhering to the operational guidelines, as gate operation currently relies too much on the discretion of the operator at the site”.

COMMENT

For Mr. Dharmasena to bring to the attention of the public that “gate operation currently relies too much on the discretion of the operator at the site”, is being disingenuous, after accepting flooding as a way of life for ALL major reservoirs for decades and not doing much about it. As far as the public is concerned, their expectation is that the Institution responsible for Reservoir Management should, not only develop the necessary guidelines to address flooding but also ensure that they are strictly administered by those responsible, without leaving it to the arbitrary discretion of field staff. This exercise should be reviewed annually after each monsoon, if lives are to be saved and livelihoods are to be sustained.

IMPACT of GATE OPERATION on FLOODING

According to Mr. Dhamasena, “Major reservoir spillways are designed for very high return periods… If the spillway gates are opened fully when reservoir is at full capacity, this can produce an artificial flood of a very large magnitude… Therefore, reservoir operators must be mindful in this regard to avoid any artificial flood creation” (Ibid). Continuing, he states: “In reality reservoir spillways are often designed for the sole safety of the reservoir structure, often compromising the safety of the downstream population. This design concept was promoted by foreign agencies in recent times to safeguard their investment for dams. Consequently, the discharge capacities of these spill gates significantly exceed the natural carrying capacity of river(s) downstream” (Ibid).

COMMENT

The design concept where priority is given to the “sole safety of the structure” that causes the discharge capacity of spill gates to “significantly exceed” the carrying capacity of the river is not limited to foreign agencies. Such concepts are also adopted by local designers as well, judging from the fact that flooding is accepted as an inevitable feature of reservoirs. Since design concepts in their current form lack concern for serious destructive consequences downstream and, therefore, unacceptable, it is imperative that the Government mandates that current design criteria are revisited as a critical part of the restoration programme.

CONNECTIVITY BETWEEN GATE OPENINGS and SAFETY MEASURES

It is only after the devastation of historic proportions left behind by Cyclone Ditwah that the Public is aware that major reservoirs are designed with spill gate openings to protect the safety of the structure without factoring in the consequences downstream, such as the safety of the population is an unacceptable proposition. The Institution or Institutions associated with the design have a responsibility not only to inform but also work together with Institutions such as Disaster Management and any others responsible for the consequences downstream, so that they could prepare for what is to follow.

Without working in isolation and without limiting it only to, informing related Institutions, the need is for Institutions that design reservoirs to work as a team with Forecasting and Disaster Management and develop operational frameworks that should be institutionalised and approved by the Cabinet of Ministers. The need is to recognize that without connectivity between spill gate openings and safety measures downstream, catastrophes downstream are bound to recur.

Therefore, the mandate for dam designers and those responsible for disaster management and forecasting should be for them to jointly establish guidelines relating to what safety measures are to be adopted for varying degrees of spill gate openings. For instance, the carrying capacity of the river should relate with a specific openinig of the spill gate. Another specific opening is required when the population should be compelled to move to high ground. The process should continue until the spill gate opening is such that it warrants the population to be evacuated. This relationship could also be established by relating the spill gate openings to the width of the river downstream.

The measures recommended above should be backed up by the judicious use of the land within the flood plain of reservoirs for “DRY DAMS” with sufficient capacity to intercept part of the spill gate discharge from which excess water could be released within the carrying capacity of the river. By relating the capacity of the DRY DAM to the spill gate opening, a degree of safety could be established. However, since the practice of demarcating flood plains is not taken seriously by the Institution concerned, the Government should introduce a Bill that such demarcations are made mandatory as part of State Land in the design and operation of reservoirs. Adopting such a practice would not only contribute significantly to control flooding, but also save lives by not permitting settlement but permitting agricultural activities only within these zones. Furthermore, the creation of an intermediate zone to contain excess flood waters would not tax the safety measures to the extent it would in the absence of such a safety net.

CONCLUSION

Perhaps, the towns of Kotmale and Gampola suffered severe flooding and loss of life because the opening of spill gates to release the unprecedented volumes of water from Cyclone Ditwah, was warranted by the need to ensure the safety of Kotmale and Upper Kotmale Dams.

This and other similar disasters bring into focus the connectivity that exists between forecasting, operation of spill gates, flooding and disaster management. Therefore, it is imperative that the government introduce the much-needed legislative and executive measures to ensure that the agencies associated with these disciplines develop a common operational framework to mitigate flooding and its destructive consequences. A critical feature of such a framework should be the demarcation of the flood plain, and decree that land within the flood plain is a zone set aside for DRY DAMS, planted with trees and free of human settlements, other than for agricultural purposes. In addition, the mandate of such a framework should establish for each river basin the relationship between the degree to which spill gates are opened with levels of flooding and appropriate safety measures.

The government should insist that associated Agencies identify and conduct a pilot project to ascertain the efficacy of the recommendations cited above and if need be, modify it accordingly, so that downstream physical features that are unique to each river basin are taken into account and made an integral feature of reservoir design. Even if such restrictions downstream limit the capacities to store spill gate discharges, it has to be appreciated that providing such facilities within the flood plain to any degree would mitigate the destructive consequences of the flooding.

By Neville Ladduwahetty



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Fractious West facing a more solidified Eastern opposition

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An Iranian attack on a neighbouring Gulf state. Image courtesy BBC.

Going forward, it is hoped that a reported ceasefire agreement between the US and Iran would provide a basis for a degree of stability in the Middle East and pave the way for substantive peace talks between the powers concerned. The world is compelled to fall back on hope because there is never knowing when President Donald Trump would change his mind and plans on matters of the first importance. So erratic has he been.

Yet, confusion abounds on who has agreed to what. The US President is on record that a number of conditions put forward by him to Iran to deescalate tensions have been accepted by the latter, whereas Iran is yet to state unambiguously that this is so. For instance, the US side claims that Iran has come clear on the point that it would not work towards acquiring a nuclear weapons capability, but there is no official confirmation by Iran that this is so. The same goes for the rest of the conditions.

Accordingly, the peace process between the US and Iran, if such a thing solidly exists, could be said to be mired in uncertainty. Nevertheless, the wider publics of the world are bound to welcome the prospects of some sort of ceasing of hostilities because it would have the effect of improving their economic and material well being which is today under a cloud.

However, questions of the first magnitude would continue to bedevil international politics and provide the breeding ground for continued tensions between East and West. Iran-US hostilities helped highlight some of these divisive issues and a deescalation of these tensions would not inevitably translate into even a temporary resolution of these questions. The world community would have no choice but to take them up and work towards comprehending them better and managing them more effectively.

For example, there are thorny questions arising from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). Essentially, this treaty bans the processing and use of nuclear weapons by states but some of the foremost powers are not signatories to it.

Moreover, the NPT does not provide for the destroying of nuclear arsenals by those signatory states which are already in possession of these WMDs. Consequently, there would be a glaring power imbalance between the latter nuclear-armed states and others which possess only conventional weapons.

Such a situation has grave implications for Iran’s security, for instance. The latter could argue, in view of the NPT restrictions, that the US poses a security threat to it but that it is debarred by the Treaty from developing a nuclear arms capability of its own to enable it to match the nuclear capability of the US. Moreover, its regional rival Israel is believed to possess a nuclear weapons capability.

Accordingly, a case could be made that the NPT is inherently unfair. The US would need to help resolve this vexatious matter going forward. But if it remains, US-Iran tensions would not prove easy to resolve. The same goes for Iran-Israeli tensions. Consequently, the Middle East would remain the proverbial ‘powder keg’.

Besides the above issues, the world has ample evidence that it could no longer speak in terms of a united NATO or West. Apparently, there could be no guarantee that US-NATO relations would remain untroubled in future, even if the current Iran-US standoff is peacefully resolved. US-NATO ties almost reached breaking point in the current crisis when the US President called on its NATO partners, particularly Britain, to help keep open the Hormuz Straits for easy navigation by commercial vessels, militarily, on seeing that such help was not forthcoming. Such questions are bound to remain sore points in intra-Western ties.

In other words, it would be imperative for the US’ NATO partners to help pull the US’ ‘chestnuts out of the fire’ going ahead. The question is, would NATO be willing to thus toe the US line even at the cost of its best interests.

For the West, these fractious issues are coming to the fore at a most unpropitious moment. The reality that could faze the West at present is the strong opposition shown to its efforts to bolster its power and influence by China and Russia. Right through the present crisis, the latter have stood by Iran, materially and morally. For instance, the most recent Security Council resolution spearheaded by the US which was strongly critical of Iran, was vetoed by China and Russia.

Accordingly, we have in the latter developments some marked polarities in international politics that could stand in the way of the West advancing its interests unchallenged. They point to progressively intensifying East-West tensions in international relations in the absence of consensuality.

It is only to be expected that given the substance of international politics that the West would be opposed by the East, read China and Russia, in any of the former’s efforts to advance its self interests unilaterally in ways that could be seen as illegitimate, but what is sorely needed at present is consensuality among the foremost powers if the world is to be ‘a less dangerous place to live in.’ Minus a focus on the latter, it would be a ‘no-win’ situation for all concerned.

It would be central to world stability for International Law to be upheld by all states and international actors. Military intervention by major powers in the internal affairs of other countries remains a principal cause of international mayhem. Both East and West are obliged to abide scrupulously with this principle.

From the latter viewpoint, not only did the West err in recent times, but the East did so as well. Iran, for instance, acted in gross violation of International Law when it attacked neighbouring Gulf states which are seen as US allies. Neither Iran nor the US-Israel combine have helped in advancing international law and order by thus taking the law into their own hands.

Unfortunately, the UN has been a passive spectator to these disruptive developments. It needs to play a more robust role in promoting world peace and in furthering consensual understanding among the principal powers in particular. The need is also urgent to advance UN reform and render the UN a vital instrument in furthering world peace. The East and West need to think alike and quickly on this urgent undertaking.

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Science-driven health policies key to tackling emerging challenges — UNFPA

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Dr. Dayanath Ranatunga

Marking World Health Day on April 7, health experts have called for a stronger commitment to science-based decision-making to address increasingly complex and evolving health challenges in Sri Lanka and beyond.

Dr. Dayanath Ranatunga, Assistant Representative of the United Nations Population Fund, stressed that health is no longer confined to hospitals or traditional medical systems, but is shaped by a broad spectrum of social, environmental, and technological factors.

“This year’s theme, ‘Together for Health. Stand with Science,’ reminds us that science is not only for laboratories or policymakers. It is a way of thinking and a tool that shapes everyday decisions,” he said.

Dr. Ranatunga noted that modern health challenges are increasingly interconnected, ranging from infectious diseases such as COVID-19 to climate-related risks, demographic shifts, and emerging forms of online violence.

He warned that maternal and newborn health continues to demand urgent attention despite progress. Globally, an estimated 260,000 women died from pregnancy and childbirth-related causes in 2023 alone—many of them preventable through timely, science-based interventions.

“In countries like Sri Lanka, where fertility rates are declining and survival rates improving, every pregnancy carries greater significance—not just for families, but for the future of communities and economies,” he said.

The UNFPA official also highlighted the growing threat of Technology Facilitated Gender-Based Violence (TFGBV), including cyber harassment and online abuse, noting that these forms of violence can have deep psychological consequences despite lacking visible physical harm.

He emphasised the need for multidisciplinary, science-informed approaches that integrate mental health, digital safety, and survivor-centered care.

Turning to demographic trends, Dr. Ranatunga pointed out that increasing life expectancy is bringing new challenges, particularly the rise of non-communicable diseases such as diabetes, cardiovascular illnesses, and cancers.

In Sri Lanka, nearly 13.9% of mothers develop diabetes during pregnancy, a trend attributed to obesity and unhealthy lifestyles, underscoring the urgent need for preventive healthcare strategies.

“Are we investing enough in prevention?” he asked, noting that early intervention and healthier lifestyles could significantly reduce long-term healthcare costs, especially in a country with a free public healthcare system.

He underscored the importance of data-driven policymaking, stating that scientific research and analytics enable governments to identify gaps, anticipate future needs, and allocate resources more effectively.

The UNFPA, he said, is already leveraging tools such as Geographic Information Systems (GIS) to improve access to maternal healthcare, including mapping travel times for pregnant women to reach health facilities.

Digital innovation is also transforming healthcare delivery, from telemedicine to real-time data systems, improving efficiency and ensuring continuity of care even during emergencies.

In Sri Lanka, partnerships between the government and development agencies are helping to modernise training institutions, including facilities in Batticaloa, equipping healthcare workers with both clinical and digital skills.

However, Dr. Ranatunga cautioned that technology alone is not a solution.

“It must be guided by evidence and grounded in equity,” he said, pointing out that women’s health remains significantly underfunded, with only about 7% of global healthcare research focusing on conditions specific to women.

He also drew attention to the growing health impacts of climate change, including extreme weather, food insecurity, and displacement, describing it as an emerging public health crisis.

“Health does not begin in hospitals. It is shaped by the environments we live in, the choices we make, and the systems we build,” he said.

Calling for renewed commitment, Dr. Ranatunga urged stakeholders to invest in prevention, embrace innovation, and ensure that science remains central to policy and practice.

“Science is not just about knowledge—it is about ensuring that everyone has the opportunity to live healthy, dignified lives, and that no one is left behind,” he added.

 

By Ifham Nizam

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Sharing the festive joy with ‘Awurudu Kaale’

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The visually impaired who make up Bright Light Band in Awurudu attire

Melantha Perera is well known as a very versatile musician.

He was involved with the band Mirage, as their keyboardist/vocalist, and was also seen in action with other outfits, as well, before embarking on a trip to Australia, as a solo artiste.

I now hear that he has plans to operate as a trio.

However, what has got many talking about Melantha, these days, is his awesome work with the visually impaired Bright Light Band.

They have worked out a special song for the Sinhala and Tamil New Year, aptly titled ‘Awurudu Kaale.

Says Melantha: “This song has been created to celebrate the spirit of the Sinhala and Tamil New Year and to share the joy of the Awurudu season with all Sri Lankans”.

Yes, of course, Melantha composed the song, with the lyrics written collaboratively by Melantha, Badra, and the parents of the talented performers, whose creative input brought the song to life during moments of inspiration.

Melantha Perera: Awesome work with Bright Light Band

This meaningful collaboration reflects the strong community behind the Bright Light Band.

According to Melantha, accompaning the song is a vibrant video production that also features the involvement of the parents, highlighting unity, joy, and togetherness.

Beyond showcasing their musical talents, the visually impaired members of Bright Light Band deliver a powerful message, through this project, that their abilities extend beyond singing, as they also express themselves through movement and dance.

Melantha expressed his satisfaction with the outcome of the project and looks forward to sharing it with audiences across the country during this festive season.

He went on to say that Bright Light Band extends its sincere gratitude to Bcert Australia for their generous Mian sponsorship, the CEO of the company, Samath Fernando, for his continuous support in making such initiatives possible, and Rukshan Perera for his personal support and encouragement in bringing this project to completion.

The band also acknowledges Udara Fernando for his invaluable contribution, generously providing studio space and accommodating extended recording sessions to suit the children’s availability.

Appreciation is warmly extended to the parents, whose unwavering commitment from ensuring attendance at rehearsals to supporting the video production has been instrumental in the success of this project.

Through ‘Awurudu Kaale’, Bright Light Band hopes to spread festive cheer and inspire audiences, proving that passion and talent know no boundaries.

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