Features

The Mahaweli

Published

5 years ago

2021/09/5

by Chanaka Wickramasuriya

“Mahaweli mahaweli mahaweli”….. Virtuoso pandit Amaradeva’s classic resonates out there as the author traces this river; geographically, along the topographical contours of this varied land, and historically, along its intricate relationship with this island’s both ancient and contemporary civilizations.

The Mahaweli, or literally ‘the great sands’, is not just a river. And it is not just the island’s longest river (at 335km), or the one with the largest river basin (10,500 of the island’s total 65,000 sq km). The Mahaweli has a natural uniqueness to it that has resulted in a profound bearing on the formation and evolution of our cultural and political heritage. It will not be presumptuous to say that this river, analogous to its meandering trace, has carved the path for the history of this island’s peoples. Or even perhaps, been responsible for the sheer existence of a history itself. Amaradeva poetically alludes to this in his classical ballad.

One can say that the Mahaweli traces its headwaters to the Kotmale Oya and Hatton Oya. The former, having its source along the north western slopes of the Horton Plains plateau, while the latter traces its beginnings along the Watawala ridge. The significance of this will not be lost to even the amateur hydrologist. An overlay of the rainfall patters of Sri Lanka on her map shows that the country’s highest annual average rainfall takes place along this range, and notably, on account of it being fed by the more prolific South West Monsoon, at almost twice the precipitation of its North East counterpart.

This makes for a remarkable fact. The Mahaweli becomes, as far as this author can ascertain, the only Dry Zone river to be fed by the South West Monsoonal rains.

Having harnessed and coalesced these waters, the Mahaweli carves an idyllic path northward along the Gampola valley. The splendor of this valley discernible to even this author, as he once sat at a hermitage on the hills of Hindagala watching this river, dotted on either side by quaint hamlets and rice fields, the vestiges of an ancient kingdom that found refuge during trying times. And alas only to be told by his mentors that he was negating the benefits of his vipassana endeavors by pleasing his senses!

The river thus meanders its way up to Gannoruwa. And here, the providence of nature, or the hands of the formative deities of this land, depending on your preference, make a call. The river encounters a small hillock at Gannoruwa, and perhaps because of it, and unlike like all rivers originating on the western slopes that carve their way down toward the western seaboard, the Mahaweli makes an abrupt right turn.

At some point in pre-history these waters would have then encountered a formidable bridge of Charnockite rock in the escarpment between the central plateau and the southern edge of the Knuckles massif. Eons of hydrological erosion then forced these waters through the gorges of Randenigala and the breathtakingly narrow Rantambe, churning out what would have then been class four and five rapids. Legend has it that the master equestrian King Rajasinghe II would leap across the narrow 20-foot gap on his trusty steed, and that until more recently when the dams of the Mahaweli Development Program took shape, the sounds of these churning waters could have been heard over five km away. Like a giant hydrological serpent, the river breaks through this East-West divide to rear its head onto the eastern half of the island. And here too the seemingly inexplicable takes place.

Having garnered further waters from the Knuckles via the Hulu Ganga, from Pidurutalagala via the Ma Oya, from Horton Plains via the Uma Oya and from even as far as the Badulla and Passara hills via the Badulu Oya and Loggal Oya, instead of finding what would look to the layman as a path of least resistance directly toward the eastern seaboard, the Mahaweli decides to turn north.

The river then traverses this almost directly northern path, covering about half of its total distance, and a third of the island, to break into the ocean via a myriad of mangrove forested deltas at the island’s largest bay at Koddiyar in Trincomalee. Here too merging into yet another natural wonder of what is one of the world’s largest natural harbors, replete with underwater chasms and gorges of over 700m deep. But not until the river has harnessed even greater waters along the way through its largest tributary, the Amban Ganga, it too a creation of the western slopes of the Knuckles range, and the less plentiful Hasalaka Oya and Heen Ganga, which gather waters off the range’s eastern slopes. In this section the Mahaweli creates what is the country’s largest deposits of alluvial soil, spanning the entirety of its northern trajectory and breaking into vast areas of up to 10km wide on account of seasonal flood plains, as well as the largest seasonal sand banks from which the river derived its name.

Thus, it is as if nature was the precursor to our island’s proud hydrological engineering heritage, and even its modern manifestation of the Mahaweli Development Program. For nature seems to have decided long ago to find a way to harness the bounty of water from the island’s salubrious western slopes and nourish its dry north-central and eastern plains. A feat of engineering even modern man would have found hard to, and is yet to, replicate.

But the story of the Mahaweli does not end there. Mankind soon pounces upon this natural marvel to both exploit and tinker with her resources for their benefit. It is akin to having been endowed with a mythical nature’s guitar, and then fine tuning its cords to seek the perfect tune. The resulting dance having spanned over two millennia yet continues. While this story could be arguably best narrated through time, this author will choose to deliver it, like the river itself, along the course of its journey.

The story begins in the upper reaches of the Kotmale Oya, the Agra Oya. Here, literally and metaphorically shrouded in the mists of the Thotupola hill and time, a little south of Pattipola, are the remnants of a little known 220m long tunnel and 11km long canal. Believed to have been constructed circa the 13-14th century, it is perhaps the earliest known subterranean trans basin canal. Considered an engineering marvel for its time, this canal used to divert the west bound waters east into the Uma Oya basin to irrigate the lush fields of the Uva.

Moving down the Kotmale Oya, further nourished by the Nanu Oya is the Upper Kotmale Reservoir and Hydro Power scheme. The third largest power generator of the Mahaweli Development Scheme originally conceived between 1965-69 under and FAO/UNDP funded master plan, this was one of the last to be completed in 2010 after a series of environmental controversies and re-engineering. The river is then joined by the waters of the Devon Oya, Pundal Oya and Ramboda Oya and flows into the famed and beautiful valley of Kotmale, once the sanctuary of the legendary King Dutugemunu during his youth. This valley was inundated by a rock-filled dam 87m high and 600m in length starting in 1978 under the Accelerated Mahaveli Development Program, becoming the second highest hydro electricity generator of the scheme. Its added function being controlling the flood waters of the Gampola valley and optimizing the diversion flow at the barrage at Polgolla.

As the Mahaweli, now as a fully-fledged river or ganga, meanders its way around the upper middle-class suburbs of Kandy, evoking visions of our checkered history with names like Primrose Gardens, Anniewatte and Mawilmada, we encounter the Polgolla Barrage. Polgolla was the first of the projects under the Mahaweli Development Program and was implemented in 1976. At 144m in length and 14.6m in height, a relatively innocuous looking structure compared to its gargantuan brethren, the Polgolla Barrage nevertheless, in this authors view, creates the most geographically impactful diversion of Mahaweli waters.

It starts with an eight km long underground penstock northward to Ukuwele power station. Ukuwele then releases these spent waters into the Dhun Oya, which in turn connects to the Sudu Ganga which then emerges further north as the Bowatenna Reservoir. Built in 1981, the picturesque Bowatenna’s primary purpose was retention and diversion of waters for irrigation. In a bizarre twist of engineering and geographical fate, the released waters of Bowatenna become the Amban Ganga, making the Mahaweli the only river to feed its own tributary.

Waters diverted from Bowatenna are channeled through a tunnel to Lenodara, and from there enter the Dambulu Oya. It is from here that modern man’s diversions of the Mahaweli start to enter the realm of the ancient kings, and their stupendous feats of hydrological engineering and civilization building.

The Dambulu Oya has a little known but unique history, as it is a conduit of Mahaweli waters from two separate modern and ancient diversions. The ancient system starting from Demada Oya, a tributary of the Amban where an anicut built by Dhatusena diverted waters to the Wilimiti Oya, a tributary of the Dambulu. The Dambulu Oya thus takes Mahaweli/Amban waters from both Dhatusena’s creation as well as the modern Bowatenna, via the Ibbankatuwa Tank, north into the gigantic Kala Wewa – Balalu wewa complex and the Kala oya basin. Dhatusena’s “only treasure” as he proclaimed, for which he earned his patricidal son Kassapa’s wrath, Kala Wewa is the largest tank complex of ancient Sri Lanka and was built in the fifth Century AD. Waters from the Kala Wewa are transferred via the famous Jaya Ganga, carved also during the same time with the intricate engineering precision of a gradient of one foot to one mile, 86km to Devanampiyatissa’s third Century BC Tissa Wewa in the ancient citadel of Anuradhapura. Waters also find their way to the more modern Rajanganaya further west via the Kala Oya itself. The excess waters of the Tissa wewa find their way into the Malwatu Oya, the islands second longest river, and off that via the Yoda Ela into the famed Giant’s Tank over 50km north west of Anuradhapura, it too a creation of the legendary Dhatusena, to irrigate the famous Rice Bowl of Mannar.

A bifurcation at Dambulu Oya built in 1976 also takes Mahaweli waters into the ancient and touristically popular Kandalama tank, the origin of which is little known, as well as to the Hurulu Wewa a further 25 km north. Built by Mahasen in the first Century AD, the Hurulu is the primary repository source of Sri Lanka’s fifth longest river, the Yan Oya, where a new reservoir was constructed in 2017 about 50km further north east. Sporting what is Sri Lanka’s longest main and saddle dams totaling a staggering six km in length, the Yan Oya project infuses water into the ancient Padaviya Tank. Originally built to trap the waters of the Ma Oya, the actual origins of this very ancient tank are yet debated but speculated to having been built by Saddhatissa (137-119 BC). 165km from its original diversion at Polgolla, this will be the furthest point north yet traversed by the Mahaweli’s waters.

But Bowatenne is not done yet in her generous dispersions of Mahaweli’s bounty. Rather coincidentally and poignantly perhaps, situated at what is considered the center of the island, the reservoir stands where the iconic Nalanda Gedige temple stood. Since relocated to the banks of the lake, this temple represents a unique fusion of Hindu and Mahayana Buddhist Tantric architecture and is thought to have been built around the 13th Century. Waters thus blessed flow beyond Bowatenna as the mighty Amban, the Mahaweli’s largest tributary, which has an ancient and contemporary history worthy of her own story.

To be continued

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Features

Ranking public services with AI — A roadmap to reviving institutions like SriLankan Airlines

Published

2 days ago

2026/03/13

Thilina Walpola

Efficacy measures an organisation’s capacity to achieve its mission and intended outcomes under planned or optimal conditions. It differs from efficiency, which focuses on achieving objectives with minimal resources, and effectiveness, which evaluates results in real-world conditions. Today, modern AI tools, using publicly available data, enable objective assessment of the efficacy of Sri Lanka’s government institutions.

Among key public bodies, the Supreme Court of Sri Lanka emerges as the most efficacious, outperforming the Department of Inland Revenue, Sri Lanka Customs, the Election Commission, and Parliament. In the financial and regulatory sector, the Central Bank of Sri Lanka (CBSL) ranks highest, ahead of the Securities and Exchange Commission, the Public Utilities Commission, the Telecommunications Regulatory Commission, the Insurance Regulatory Commission, and the Sri Lanka Standards Institution.

Among state-owned enterprises, the Sri Lanka Ports Authority (SLPA) leads in efficacy, followed by Bank of Ceylon and People’s Bank. Other institutions assessed included the State Pharmaceuticals Corporation, the National Water Supply and Drainage Board, the Ceylon Electricity Board, the Ceylon Petroleum Corporation, and the Sri Lanka Transport Board. At the lower end of the spectrum were Lanka Sathosa and Sri Lankan Airlines, highlighting a critical challenge for the national economy.

Sri Lankan Airlines, consistently ranked at the bottom, has long been a financial drain. Despite successive governments’ reform attempts, sustainable solutions remain elusive.

Globally, the most profitable airlines operate as highly integrated, technology-enabled ecosystems rather than as fragmented departments. Operations, finance, fleet management, route planning, engineering, marketing, and customer service are closely coordinated, sharing real-time data to maximise efficiency, safety, and profitability.

The challenge for Sri Lankan Airlines is structural. Its operations are fragmented, overly hierarchical, and poorly aligned. Simply replacing the CEO or senior leadership will not address these deep-seated weaknesses. What the airline needs is a cohesive, integrated organisational ecosystem that leverages technology for cross-functional planning and real-time decision-making.

The government must urgently consider restructuring Sri Lankan Airlines to encourage:

=Joint planning across operational divisions

=Data-driven, evidence-based decision-making

=Continuous cross-functional consultation

=Collaborative strategic decisions on route rationalisation, fleet renewal, partnerships, and cost management, rather than exclusive top-down mandates

Sustainable reform requires systemic change. Without modernised organisational structures, stronger accountability, and aligned incentives across divisions, financial recovery will remain out of reach. An integrated, performance-oriented model offers the most realistic path to operational efficiency and long-term viability.

Reforming loss-making institutions like Sri Lankan Airlines is not merely a matter of leadership change — it is a structural overhaul essential to ensuring these entities contribute productively to the national economy rather than remain perpetual burdens.

By Chula Goonasekera – Citizen Analyst

Features

Why Pi Day?

Published

2 days ago

2026/03/13

Thilina Walpola

International Day of Mathematics falls tomorrow

The approximate value of Pi (π) is 3.14 in mathematics. Therefore, the day 14 March is celebrated as the Pi Day. In 2019, UNESCO proclaimed 14 March as the International Day of Mathematics.

Ancient Babylonians and Egyptians figured out that the circumference of a circle is slightly more than three times its diameter. But they could not come up with an exact value for this ratio although they knew that it is a constant. This constant was later named as π which is a letter in the Greek alphabet.

Archimedes

It was the Greek mathematician Archimedes (250 BC) who was able to find an upper bound and a lower bound for this constant. He drew a circle of diameter one unit and drew hexagons inside and outside the circle such that the sides of each hexagon touch the sides of the circle. In mathematics the circle passing through all vertices of a polygon is called a ‘circumcircle’ and the largest circle that fits inside a polygon tangent to all its sides is called an ‘incircle’. The total length of the smaller hexagon then becomes the lower bound of π and the length of the hexagon outside the circle is the upper bound. He realised that by increasing the number of sides of the polygon can make the bounds get closer to the value of Pi and increased the number of sides to 12,24,48 and 60. He argued that by increasing the number of sides will ultimately result in obtaining the original circle, thereby laying the foundation for the theory of limits. He ended up with the lower bound as 22/7 and the upper bound 223/71. He could not continue his research as his hometown Syracuse was invaded by Romans and was killed by one of the soldiers. His last words were ‘do not disturb my circles’, perhaps a reference to his continuing efforts to find the value of π to a greater accuracy.

Archimedes can be considered as the father of geometry. His contributions revolutionised geometry and his methods anticipated integral calculus. He invented the pulley and the hydraulic screw for drawing water from a well. He also discovered the law of hydrostatics. He formulated the law of levers which states that a smaller weight placed farther from a pivot can balance a much heavier weight closer to it. He famously said “Give me a lever long enough and a place to stand and I will move the earth”.

Mathematicians have found many expressions for π as a sum of infinite series that converge to its value. One such famous series is the Leibniz Series found in 1674 by the German mathematician Gottfried Leibniz, which is given below.

π = 4 ( 1 – 1/3 + 1/5 – 1/7 + 1/9 – ………….)

The Indian mathematical genius Ramanujan came up with a magnificent formula in 1910. The short form of the formula is as follows.

π = 9801/(1103 √8)

For practical applications an approximation is sufficient. Even NASA uses only the approximation 3.141592653589793 for its interplanetary navigation calculations.

It is not just an interesting and curious number. It is used for calculations in navigation, encryption, space exploration, video game development and even in medicine. As π is fundamental to spherical geometry, it is at the heart of positioning systems in GPS navigations. It also contributes significantly to cybersecurity. As it is an irrational number it is an excellent foundation for generating randomness required in encryption and securing communications. In the medical field, it helps to calculate blood flow rates and pressure differentials. In diagnostic tools such as CT scans and MRI, pi is an important component in mathematical algorithms and signal processing techniques.

This elegant, never-ending number demonstrates how mathematics transforms into practical applications that shape our world. The possibilities of what it can do are infinite as the number itself. It has become a symbol of beauty and complexity in mathematics. “It matters little who first arrives at an idea, rather what is significant is how far that idea can go.” said Sophie Germain.

Mathematics fans are intrigued by this irrational number and attempt to calculate it as far as they can. In March 2022, Emma Haruka Iwao of Japan calculated it to 100 trillion decimal places in Google Cloud. It had taken 157 days. The Guinness World Record for reciting the number from memory is held by Rajveer Meena of India for 70000 decimal places over 10 hours.

Happy Pi Day!

The author is a senior examiner of the International Baccalaureate in the UK and an educational consultant at the Overseas School of Colombo.

by R N A de Silva

Features

Sheer rise of Realpolitik making the world see the brink

Published

3 days ago

2026/03/12

Sahan Weerasooriya

A combined US-Israel attack on Iran.(BBC)

The recent humanly costly torpedoing of an Iranian naval vessel in Sri Lanka’s Exclusive Economic Zone by a US submarine has raised a number of issues of great importance to international political discourse and law that call for elucidation. It is best that enlightened commentary is brought to bear in such discussions because at present misleading and uninformed speculation on questions arising from the incident are being aired by particularly jingoistic politicians of Sri Lanka’s South which could prove deleterious.

As matters stand, there seems to be no credible evidence that the Indian state was aware of the impending torpedoing of the Iranian vessel but these acerbic-tongued politicians of Sri Lanka’s South would have the local public believe that the tragedy was triggered with India’s connivance. Likewise, India is accused of ‘embroiling’ Sri Lanka in the incident on account of seemingly having prior knowledge of it and not warning Sri Lanka about the impending disaster.

It is plain that a process is once again afoot to raise anti-India hysteria in Sri Lanka. An obligation is cast on the Sri Lankan government to ensure that incendiary speculation of the above kind is defeated and India-Sri Lanka relations are prevented from being in any way harmed. Proactive measures are needed by the Sri Lankan government and well meaning quarters to ensure that public discourse in such matters have a factual and rational basis. ‘Knowledge gaps’ could prove hazardous.

Meanwhile, there could be no doubt that Sri Lanka’s sovereignty was violated by the US because the sinking of the Iranian vessel took place in Sri Lanka’s Exclusive Economic Zone. While there is no international decrying of the incident, and this is to be regretted, Sri Lanka’s helplessness and small player status would enable the US to ‘get away with it’.

Could anything be done by the international community to hold the US to account over the act of lawlessness in question? None is the answer at present. This is because in the current ‘Global Disorder’ major powers could commit the gravest international irregularities with impunity. As the threadbare cliché declares, ‘Might is Right’….. or so it seems.

Unfortunately, the UN could only merely verbally denounce any violations of International Law by the world’s foremost powers. It cannot use countervailing force against violators of the law, for example, on account of the divided nature of the UN Security Council, whose permanent members have shown incapability of seeing eye-to-eye on grave matters relating to International Law and order over the decades.

The foregoing considerations could force the conclusion on uncritical sections that Political Realism or Realpolitik has won out in the end. A basic premise of the school of thought known as Political Realism is that power or force wielded by states and international actors determine the shape, direction and substance of international relations. This school stands in marked contrast to political idealists who essentially proclaim that moral norms and values determine the nature of local and international politics.

While, British political scientist Thomas Hobbes, for instance, was a proponent of Political Realism, political idealism has its roots in the teachings of Socrates, Plato and latterly Friedrich Hegel of Germany, to name just few such notables.

On the face of it, therefore, there is no getting way from the conclusion that coercive force is the deciding factor in international politics. If this were not so, US President Donald Trump in collaboration with Israeli Rightist Premier Benjamin Natanyahu could not have wielded the ‘big stick’, so to speak, on Iran, killed its Supreme Head of State, terrorized the Iranian public and gone ‘scot-free’. That is, currently, the US’ impunity seems to be limitless.

Moreover, the evidence is that the Western bloc is reuniting in the face of Iran’s threats to stymie the flow of oil from West Asia to the rest of the world. The recent G7 summit witnessed a coming together of the foremost powers of the global North to ensure that the West does not suffer grave negative consequences from any future blocking of western oil supplies.

Meanwhile, Israel is having a ‘free run’ of the Middle East, so to speak, picking out perceived adversarial powers, such as Lebanon, and militarily neutralizing them; once again with impunity. On the other hand, Iran has been bringing under assault, with no questions asked, Gulf states that are seen as allying with the US and Israel. West Asia is facing a compounded crisis and International Law seems to be helplessly silent.

Wittingly or unwittingly, matters at the heart of International Law and peace are being obfuscated by some pro-Trump administration commentators meanwhile. For example, retired US Navy Captain Brent Sadler has cited Article 51 of the UN Charter, which provides for the right to self or collective self-defence of UN member states in the face of armed attacks, as justifying the US sinking of the Iranian vessel (See page 2 of The Island of March 10, 2026). But the Article makes it clear that such measures could be resorted to by UN members only ‘ if an armed attack occurs’ against them and under no other circumstances. But no such thing happened in the incident in question and the US acted under a sheer threat perception.

Clearly, the US has violated the Article through its action and has once again demonstrated its tendency to arbitrarily use military might. The general drift of Sadler’s thinking is that in the face of pressing national priorities, obligations of a state under International Law could be side-stepped. This is a sure recipe for international anarchy because in such a policy environment states could pursue their national interests, irrespective of their merits, disregarding in the process their obligations towards the international community.

Moreover, Article 51 repeatedly reiterates the authority of the UN Security Council and the obligation of those states that act in self-defence to report to the Council and be guided by it. Sadler, therefore, could be said to have cited the Article very selectively, whereas, right along member states’ commitments to the UNSC are stressed.

However, it is beyond doubt that international anarchy has strengthened its grip over the world. While the US set destabilizing precedents after the crumbling of the Cold War that paved the way for the current anarchic situation, Russia further aggravated these degenerative trends through its invasion of Ukraine. Stepping back from anarchy has thus emerged as the prime challenge for the world community.