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Mahaweli Project – North Central Province canal: A tunnel in the wilderness?

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by Eng. L.V. Talagala
C Eng., B Sc. Eng (Cey), M Sc (Southampton), MIE. MASCE
former Director (System B&C), Mahaweli Engineering and Construction Agency of Mahaweli Authority of Sri Lanka.


The Mahaweli Multi-Purpose Development Project is based on the Master Plan for maximum utilisation of water resources of the Mahaweli Ganga, prepared in 1965/68. The plan envisages development of 360,000 ha of irrigable land, mainly in the dry Zone in Mahaweli and adjoining river basins designated as Systems A to M, as well as 900 MW of Hydropower. The works involve the construction of several Dams and river diversion structures, together with a network of tunnels and canals.

During the 1970-77 period the Polgolla and Bowatenna river diversion works with power stations, improvements to Kalawewa, together with some land development works in the Kala Oya basin, feeder canal to Huruluwewa, and widening of Elahera Minneriya Yoda Ela were completed. Since 1977, under the Accelerated Mahaweli Development Programme, five major projects Viz, Kotmale, Victoria, Randenigala, Rantembe and Maduru Oya Dams and Hydropower plants with the total potential of around 600 MW , downstream development of about 112,000 ha in Systems B, C, H and G, and settlement of around 100,000 farmer families were carried out. A total of around Rs,1000 m (approx. 900 m US$) has been invested and direct benefits were accrued through hydropower and agricultural production. The completed projects continue to make a significant contribution to the national economy.

The current development works commenced in 2007, after Feasibility and Environmental studies, with the construction of the Moragahakanda and Kaluganga reservoirs in the Ambanganga basin. These were completed in 2018 and 2022 respectively, at a cost of over 400 m US$, and are linked together by short canals and tunnels. The combined storage capacity is around 700 million cubic meters(mcm), which is more than the capacity of Minneriya, Parakrama Samudra, Kaudulla and Kantalai tanks together.

The water stored in these reservoirs have to be conveyed to the designated areas in the North Central and Northern Provinces for agriculture. The conveyance waterway, from Moragahakanda, is called the North Central Province Canal (Ref. Fig 1). The first 20 km of the waterway runs parallel to the existing Elahera Minneriya Yoda Ela (EMYE) on a higher elevation contour and gradually turns in a Northerly direction along the centre spinal ridge that divides the river basins flowing to the west and eastern coasts of the island to end at Chennadikulam tank. This would be the most expensive and the longest (155 km approx.) waterway in Sri Lanka.

The construction work is undertaken under the North Central Province Canal Project (NCPCP) in two stages and implemented by the Mahaweli Water Security Investment Project (MWSIP) under the Ministry of Irrigation with ADB funding. A sum of around 600 m US$ is committed for the next few years for the construction of NCPCP Stage 1 works and is expected to be completed in 2026. The work involved for Stage 2 is yet to be finalized and would cost over 500 m US$. Additional costs will be incurred for Downstream Development works including the provision of irrigation facilities for the agricultural lands. (See Fig 1 and Fig 2)

North Central Province Canal Project (NCPCP) – Stage 1

(also referred to as Upper Elahera Canal (UEC) (Ref. Fig 2)

The NCPCP Stage 1 works involve

the construction of the first 65 km, of the conveyance waterway of capacity 40 m3/s, with 27 km long Tunnel and the upstream and downstream canal sections, for conveyance of water from Moragahakanda reservoir to a Trifurcation structure at Yakalla close to Huruluwewa. From this Trifurcation structure three branch canals will take off. One feeding Manankattiya, Eruwewa and Mahakanadarawa tanks in the Anuradhapura district. The second to Huruluwewa tank and the third branch will be an extension of UEC (NCPCP Stage 2), a further around 90 km up to Chennadikulam around Vavuniya, to feed new and existing tanks for development of mainly new lands. It is expected to convey around 500 mcm of water after Stage 1 and a further 500 mcm after Stage 2, a total of around 1000 mcm at final completion. Accordingly, only around 50 %of the tunnel capacity will be utilized on completion of Stage 1.

The canal sections should be completed at the time when the Tunnel, which is progressing satisfactorily with 2 Tunnel Boring Machines (TBM), is completed in 2026 to convey water to the expected destinations. The water conveyed at such high cost, is so precious, like gold, at this point and each cubic metre should be used wisely to obtain the best economic returns as soon as it is available.

Water Availability – Stage 1

Moragahakanda Reservoir of storage capacity of around 550 mcm is the focal point for water distribution of the system. It receives water from its own catchment through Ambanganga, Mahaweli water from Polgolla through Bowatenna and from the Kaluganga reservoir through the Link canal. After meeting the present commitments to the Elahera Anicut and additional requirements to meet. deficits in the tanks fed by the Elahera Anicut, the water availability for diversion through Stage 1 works at the Trifurcation structure at Yakalla is estimated at around 450 mcm. This is a very large quantity equivalent to about the combined storage capacity of four major irrigation tanks, viz Minneriya, Kaudulla, Parakrama Samudraya and Kantale.

From the Trifurcation at Yakalla, around 110 mcm will be diverted through branch canals, to the designated existing tanks in the Anuradhapura district to meet the irrigation deficits and water supply requirements. Accordingly, around 450-110 = 340 mcm of water is available for development of new lands for irrigated agriculture through the extension of the UEC.

Downstream Development

Downstream Development is the term used for the land development and provision of irrigation facilities for agriculture together with the social and other facilities for maximum production. Getting carried away with large dams, vast expanses of water, long tunnels, with sophisticated tunnelling equipment, and other heavy engineering works and to forget the downstream development activities has to be resisted.

With possible savings in water use, there would be at least around 350 mcm, equivalent to about the combined capacity of Minneriya, Kaudulla and Kantale tanks, for the development of at least 15,000 ha (40,000 ac) at a water usage duty of 2m. The area can be increased with time with efficient water management practices.

Sri Lanka is now nearly self-sufficient in rice and further investment to increase extent under Paddy cultivation is not needed. What is necessary is to enhance paddy yields to feed the increasing population. It is now essential to cultivate other crops for import substitution, for exports and to create allied economic activities in the newly developed lands. Hence all efforts need to be directed for modernized intensive irrigated agriculture as the President emphasizes in most of his speeches and discussions with relevant officials. Engagement of the Private Sector in this effort may be useful with suitable government administrative mechanisms to realize the desired objective.

A complex set of activities will be involved in the Planning and Construction of downstream development works with relevant items for consideration are identified below.

* Identification of probable land considering proximity to conveyance system, ownership, resettlement issues, etc.

* Suitability for agriculture, soil types etc.

* Selection of crops (cash crops, sugar cane, fruit, vegetables, horticulture, and other high value crops), Cropping Calendar, etc. Paddy under flood irrigation should not be encouraged except in existing small tank cascades.

* Settlement planning activities, selection of suitable farmers etc.

* The present system of allocation of 1 ha to each farmer has led to subsistence farming, with many continuing to be below the poverty line, and sustainable intensive irrigated agriculture envisaged would not materialize. New workable model to be worked out (E.g. Cooperative societies made up of individual farmers to run a large extent, Management by private companies with emphasis on the commercial aspect, Mechanization, etc.). Private investment in on-farm development including modern irrigation methods (furrow, sprinkler, drip irrigation, harnessing groundwater, etc.) to be encouraged.

* Farmer organizations should be more involved in equitable water distribution, facilitate agricultural services to farmers, marketing aspects, etc., and less on political activities.

* Design and Construction of irrigation facilities to suit cropping systems and farming models. Designs to incorporate measures for reduction of seepage losses, canal controls, night storage, reuse systems, demand water issues, conjunctive water use and other state of the art systems. Extension of UEC may be needed, if so design to required capacity with provision for future expansion

* Environmental, Wildlife and forest conservation.

* Provision of social infrastructure facilities.

* Marketing and Storage facilities. This aspect is very important as previous attempts for crop diversification failed manly due to lack of proper storage and marketing facilities

* Packaging, Processing and Agroindustry.

* On-farm Water Management and O&M

* Other related activities

All these activities should be in place with related infrastructure to utilize this golden resource, probably by the end of 2026. Completion of all Stage 1 construction works; downstream infrastructure works and development activities should be taken up immediately as a priority. If all activities are not properly planned and implemented the huge investment made would lie idle without yielding any return and only add to the debt burden.

North Central Province Canal Project (NCPCP) – Stage 2

The Stage 1 conveyance system (UEC) has been designed for 40 m3/s discharge capacity and expected to convey around 1000 mcm annually, on the basis that an additional 500 mcm is diverted from Randenigala and tapping water resources in Hasalaka and Heenganga tributaries on the eastern slope of the Knuckles range on-route to Kalu ganga during Stage 2 works.

Water Availability

At planning stage, it is intended to transfer around 500 mcm of water from Randenigala reservoir to Kaluganga and then to Moragahakanda reservoir through a system of Canals, Tunnels and Dams (Total length of around 40 km) This configuration would cause a huge loss (almost 25%) of peak power at existing power stations of Randenigala and Rantembe, which is not acceptable. In addition, there will be a reduction of water issues for irrigation from Minipe Anicut into systems B, C and E. Therefore, alternative conveyance routes and water sources have to be identified for conveyance of more water, around 500 mcm, through NCPCP Stage 2 works into Moragahakanda Reservoir.

An alternative conveyance route (Ref. Fig 3) is to let all water pass through power stations at Randenigala and Rantembe up to the Minipe Anicut, as at present, and then to divert the excess, through LB canal up to Existing Hasalaka reservoir. From here water to be pumped, may be in 2 Stages as a high lift will be involved, to the new upper Hasalaka Reservoir on the planned Randenigala Kaluganga route and then to follow the planned route through Heenganga into the Kaluganga reservoir.

The advantages of this alternative are that,

(i) there will be no reduction in power at existing Power stations at Randenigala and Rantembe,

(ii) not necessary to hold Randenigala (FSL 232) at high water level to allow gravity flow into Kaluganga (FSL 210). avoid expensive Tunnel (20 km) and inlet, outlet structures from Randenigala to Upper Hasalaka Oya lying through environmentally sensitive forest land in the Knuckles range and also avoid difficult operational conditions.

(iii) the possibility of incorporating Pump storage systems to generate Hydropower with the Pumping stations on the Reservoir cascade, of Upper, Intermediate and existing, dams on Hasalaka Oya.

(iv) no reduction of irrigation issues and curtailment of future developments in System B.

(v) less expensive than the proposed configuration.

The disadvantages are that

(i) power requirement for Pump stations at Hasalaka Reservoirs and associated operating costs. This can be overcome as Pump stations can operate at non peak hours with pump storage systems, and solar power can also be used for pumping.

(ii) the existing Minipe canal would have to carry the increased discharge. Whether the present canal can carry the additional discharge needs to be studied. If not, widening may be necessary mainly in the cut sections and probably modification of some structures. All depends on the water availability and at what time.

Another option, as suggested in previous studies, is to pump the drainage water in Mahaweli at Kalinga Nuwara to a new reservoir at Angamedilla and then to pump into Minneriya. This amount of water can be reduced from Moragahakanda issues to Elahera and transferred through the NCPCP.

A combination of both options may be necessary to meet the full requirement of the NCPCP, and need to be decided after further studies

Downstream Development

Together with the works of the extension of the NCPCP from Yakalla Trifurcation Northwards to the Chennadikulam a distance of around 90 km and the associated downstream development of the new lands needs to be undertaken. A large extent of new lands in systems J, K, L and M are available for development. It will be necessary to improve the existing tanks and construct new reservoirs to utilize the runoff in the basins during the rainy season and use the water from NCPCP to supplement the available water resources. (See Fig. 3)

4. Conclusions

While retaining the present emphasis on completing the infrastructure of NCPCP Stage 1 by 2026, with ADB funding it is necessary to focus on the downstream development works and activities to realize benefits as early as possible.

The water balance studies need to be updated with operational data from the new reservoirs and with pragmatic assumptions before commencement of NCPCP Stage 2 works to ensure that the new infrastructure built is not over designed.

The investment is too large for decision making on water resources allocations, when and where to invest to be left to an implementation agency, funding agency and consultancy firms. Establishment of a high-level steering committee with advice from multidisciplinary technical experts for directing and monitoring all activities is suggested.

Note
All analyses are based on the experience and studies made by the author with data and information from EIA report (MCB, Jun 2014, Updated Master Plan Study (SMEC 2016), MASL and ID websites and other sources.



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Features

Pharmaceuticals, deaths, and work ethics

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Yet again, deaths caused by questionable quality pharmaceuticals are in the news. As someone who had worked in this industry for decades, it is painful to see the way Sri Lankans must face this tragedy repeatedly when standard methods for avoiding them are readily available. An article appeared in this paper (Island 2025/12/31) explaining in detail the technicalities involved in safeguarding the nation’s pharmaceutical supply. However, having dealt with both Western and non-Western players of pharmaceutical supply chains, I see a challenge that is beyond the technicalities: the human aspect.

There are global and regional bodies that approve pharmaceutical drugs for human use. The Food and Drug Administration (USA), European Medicines Agency (Europe), Medicine and Health Products Regulatory Agency (United Kingdom), and the Pharmaceuticals and Medical Devices Agency (Japan) are the major ones. In addition, most countries have their own regulatory bodies, and the functions of all such bodies are harmonized by the International Council for Harmonization (ICH) and World Health Organization (WHO). We Sri Lankan can take solace in knowing that FDA, the premier drug approval body, came into being in 1906 because of tragedies similar to our own. Following the Elixir Sulfanilamide tragedy that resulted in over one hundred deaths in 1938 and the well-known Phthalidomide disaster in 1962, the role and authority of FDA has increased to ensure the safety and efficacy of the US drug supply.

Getting approval for a new proprietary pharmaceutical is an expensive and time-consuming affair: it can take many billions of dollars and ten to fifteen years to discover the drug and complete all the necessary testing to prove safety and efficacy (Island 2025/01/6). The proprietary drugs are protected by patents up to twenty years, after which anyone with the technical knowhow and capabilities can manufacture the drug, call generics, and seek approval for marketing in countries of their choice. This is when the troubles begin.

Not having to spend billions on discovery and testing, generics manufactures can provide drugs at considerable cost savings. Not only low-income countries, but even industrial countries use generics for obvious reasons, but they have rigorous quality control measures to ensure efficacy and safety. On the other hand, low-income countries and countries with corrupt regulatory systems that do not have reasonable quality control methods in place become victims of generic drug manufacturers marketing substandard drugs. According to a report, 13% of the drugs sold in low-income countries are substandard and they incur $200 billion in economic losses every year (jamanetworkopen.2018). Sri Lankans have more reasons to be worried as we have a history of colluding with scrupulous drug manufactures and looting public funds with impunity; recall the immunoglobulin saga two years ago.

The manufacturing process, storage and handling, and the required testing are established at the time of approval; and they cannot be changed without the regulatory agency’s approval. Now a days, most of the methods are automated. The instruments are maintained, operated, and reagents are handled according to standard operating procedures. The analysts are trained and all operations are conducted in well maintained laboratories under current Good Manufacturing Procedures (cGMP). If something goes wrong, there is a standard procedure to manage it. There is no need for guess work; everything is done following standard protocols. There is traceability; if something went wrong, it is possible to identify where, when, and why it happened.

Setting up a modern analytical laboratory is expensive, but it may not cost as much as a new harbor, airport, or even a few kilometers of new highway. It is safe to assume that some private sector organizations may already have a couple of them running. Affordability may not be a problem. But it is sad to say that in our part of the world, there is a culture of bungling up the best designed system. This is a major concern that Western pharmaceutical companies and regulatory agencies have in incorporating supply chains or services from our part of the world.

There are two factors that foster this lack of work ethics: corruption and lack of accountability. Admirably, the private sector has overcome this hurdle for the most part, but in the public sector, from top to bottom, lack of accountability and corruption have become a pestering cancer debilitating the economy and progress. Enough has been said about corruption, and fortunately, the present government is making an effort to curb it. We must give them some time as only the government has changed, not the people.

On the other hand, lack of accountability is a totally alien concept for our society. In many countries, politicians are held accountable at elections. We give them short breaks, to be re-elected at the next election, often with super majorities, no matter how disastrous their actions were. When it comes to government servants, we have absolutely no way to hold them accountable. There is absolutely no mechanism in place; it appears that we never thought about it.

Lack of accountability refers to the failure to hold individuals responsible for their actions. This absence of accountability fosters a culture of impunity, where corrupt practices can thrive without fear of repercussions. In Sri Lanka, a government job means a lifetime employment. There is no performance evaluation system; promotions and pay increases are built in and automatically implemented irrespective of the employee’s performance or productivity. The worst one can expect for lapses in performance is a transfer, where one can continue as usual. There is no remediation. To make things worse, often the hiring is done for political reasons rather than on merit. Such employees have free rein and have no regard for job responsibilities. Their managers or supervisors cannot take actions as they have their political masters to protect them.

The consequences of lack of accountability in any area at any level are profound. There is no need to go into detail; it is not hard to see that all our ills are the results of the culture of lack of accountability, and the resulting poor work ethics. Not only in the pharmaceuticals arena, but this also impacts all aspects of products and services available. If anyone has any doubts, they should listen to COPE committee meetings. Without a mechanism to hold politicians, government employees, and bureaucrats accountable for their actions or lack of it, Sri Lanka will continue to be a developing country forever, as has happened over the last seventy years. As a society, we must take collective actions to demand transparency, hold all those in public service accountable, and ensure that nation’s resources are used for the benefit of all citizens. The role of ethical and responsible journalism in this respect should not be underestimated.

by Geewananda Gunawardana, Ph.D. ✍️

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Tips for great sleep

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Although children can sleep well, most adults have trouble getting a good night’s sleep. They go to bed each night, but find it difficult to sleep. While in bed they toss and turn until daybreak. Such people cannot be expected to do any work properly. Upon waking they get ready to go for work, but they feel exhausted. While travelling to workplaces they doze off on buses and trains. In fact sleep deprivation leads to depression. Then they seek medical help to get over the problem.

Some people take sleeping pills without consulting a doctor. Sleeping pills might work for a few days, but you will find it difficult to drag yourself out of bed. What is more, you will feel drowsy right throughout the day. If you take sleeping pills regularly, you will get addicted to them.

A recent survey has revealed that millions of Asians suffer from insomnia – defined as an inability to fall asleep or to sleep through the night. When you do not get enough sleep for a long time, you might need medical treatment. According to a survey by National University Hospital in Singapore, 15 percent of people in the country suffer from insomnia. This is bad news coming from a highly developed country in Asia. It is estimated that one third of Asians have trouble sleeping. As such it has become a serious problem even for Sri Lankans.

Insomnia

Those who fail to take proper treatment for insomnia run the risk of sleep deprivation. A Japanese study reveals that those who sleep five hours or less are likely to suffer a heart attack. A healthy adult needs at least seven hours of sleep every day. When you do not get the required number of hours for sleep, your arteries may be inflamed. Sleep deprived people run the risk of contracting diabetes and weight gain. An American survey reveals that children who do not get deep sleep may be unnaturally small. This is because insomnia suppresses growth hormones.

It is not the length of sleep that matters. The phases of sleep are more important than the number of hours you sleep. Scientists have found that we go through several cycles of 90 minutes per night. Every cycle consists of three phases: light sleep, slumber sleep and dream sleep. When you are in deep sleep your body recuperates. When you dream your mind relaxes. Light sleep is a kind of transition between the two.

Although adults should get a minimum seven hours of sleep, the numbers may vary from person to person. In other words, some people need more than seven hours of sleep while others may need less. After the first phase of light sleep you enter the deep sleep phase which may last a few minutes. The time you spend in deep sleep may decrease according to the proportion of light sleep and dream sleep.

Napoleon Bonaparte

It is strange but true that some people manage with little sleep. They skip the light sleep and recuperate in deep sleep and dream sleep. For instance, Napoleon Bonaparte used to sleep only for four hours a night. On the other hand, we sleep at different times of the day. Some people – known as ‘Larks’ – go to bed as early as 8 p.m. There are ‘night owls’ who go to bed after midnight. Those who go to bed late and get up early are a common sight. Some of them nod off in the afternoon. This shows that we have different sleep rhythms. Dr Edgardo Juan L. Tolentino of the Philippine Department of Health says, “Sleep is as individual as our thumb prints and patterns can vary over time. Go to bed only when you are tired and not because it’s time to go to bed.”

If you are suffering from sleep deprivation, do not take any medication without consulting a doctor. Although sleeping pills can offer temporary relief, you might end up as an addict. Therefore take sleeping pills only on a doctor’s prescription. He will decide the dosage and the duration of the treatment. What is more, do not increase the dose yourself and also do not take them with alcohol.

You need to exercise your body in order to keep it in good form. However, avoid strenuous exercises late in the evening because they would stimulate the body and increase the blood circulation. This does not apply to sexual activity which will pave the way for sound sleep. If you are unable to enjoy sleep, have a good look at your bedroom. The bedroom and the bed should be comfortable. You will also fall asleep easily in a quiet bedroom. Avoid bright lights in the bedroom. Use curtains or blinds to darken the bedroom. Use a quality mattress with proper back support.

Methods

Before consulting a doctor, you may try out some of the methods given below:

* Always try to eat nutritious food. Some doctors advise patients to take a glass of red wine before going to bed. However, too much alcohol will ruin your sleep. Avoid smoking before going to bed because nicotine impairs the quality of sleep.

* Give up the habit of drinking a cup of coffee before bedtime because caffeine will keep you awake. You should also avoid eating a heavy meal before going to bed. A big meal will activate the digestive system and it will not allow the body to wind down.

* Always go to bed with a relaxed mind. This is because stress hormones in the body can hinder sleep. Those who lead stressful lives often have trouble sleeping. Such people should create an oasis between the waking day’s events and going to bed. The best remedy is to go to bed with a novel. Half way through the story you will fall asleep.

* Make it a point to go to bed at a particular time every day. When you do so, your body will get attuned to it. Similarly, try to get up at the same time every day, including holidays. If you do so, such practices will ensure your biological rhythm.

* Avoid taking a long nap in the afternoon. However, a power nap lasting 20 to 30 minutes will revitalise your body for the rest of the day.

* If everything fails, seek medical help to get over your problem.

(karunaratners@gmail.com)

By R.S. Karunatne

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Environmental awareness and environmental literacy

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A file picture of floods in Gampaha. Courtesy UNICEF/InceptChange

Two absolutes in harmonising with nature as awareness sparks interest – Literacy drives change

Hazards teach lessons to humanity.

Before commencing any movement to eliminate or mitigate the impact of any hazard there are two absolutes, we need to pay attention to. The first requirement is for the society to gain awareness of the factors that cause the particular hazard, the frequency of its occurrence, and the consequences that would follow if timely action is not taken. Out of the three major categories of hazards that have been identified as affecting the country, namely, (i) climatic hazards (floods, landslides, droughts), (ii) geophysical hazards (earthquakes, tsunamis), and (iii) endemic hazards (dengue, malaria), the most critical category that frequently affect almost all sectors is climatic hazards. The first two categories are natural hazards that occur independently of human intervention. In most instances their occurrence and behaviour are indeterminable. Endemic hazards are a combination of both climatic hazards and human negligence.

ENVIRONMENTAL AWARENESS

‘In Ceylon it never rains but pours’ – Cyclone Ditwah and Our Experiences

Climatic hazards, as experienced in Sri Lanka are dependent on nature, timing and volume of rainfall received during a year. The patterns of rainfall received indicate that, in most instances, rainfalls follow a rhythmic pattern, and therefore, their advent and ferocity as well as duration could in most instances be forecast with near accuracy. Based on analyses of long-term mean monthly rainfall data, Dr. George Thambyahpillay (Citation, University of Ceylon Review vol. XVI No. 3 & 4 Jul.-Oct 1958, pp 93-106 1958) produced a research paper wherein he exposed a certain Rainfall Rhythm in Ceylon. He opens his paper with the statement ‘In Ceylon it never rains but it pours’, which clearly shows both the velocity and the quantum of rain that falls in the island. ‘It is an idiom which expresses that ‘when one bad thing happens, a lot of other bad things also happen, making the situation even worse’. How true it is, when we reminisce short and long term impacts of the recent Ditwah cyclone.

Proving the truism of the above phrase we have experienced that many climatic hazards have been associated with the two major seasonal rainy phases, namely, the Southwest and Northeast monsoons, that befall in the two rainy seasons, May to September and December to February respectively. This pattern coincides with the classification of rainy seasons as per the Sri Lanka Met Department; 1) First inter-monsoon season – March-April, 2) Southwest monsoon – May- September, 3) Second Inter-monsoon season – October-November, and 4) Northeast monsoon – December-February.

Table 1

The table appearing below will clearly show the frequency with which climatic hazards have affected the country. (See Table 1: Notable cyclones that have impacted Sri Lanka from 1964-2025 (60 years)

A marked change in the rainfall rhythm experienced in the last 30 years

An analysis of the table of cyclones since 1978 exposes the following important trends:

(i) The frequency of occurrence of cyclones has increased since 1998,

(ii) Many cyclones have affected the northern and eastern parts of the country.

(iii) Ditwah cyclone diverged from this pattern as its trajectory traversed inland, affecting the entire island. (similar to cyclones Roanu and Nada of 2016).

(iv) A larger number of cyclones occur during the second inter-monsoon season during which Inter-Monsoonal Revolving Storms frequently occur, mainly in the northeastern seas, bordering the Bay of Bengal. Data suggests the Bay of Bengal has a higher number of deadlier cyclones than the Arabian Sea.

(v) Even Ditwah had been a severe cyclonic outcome that had its origin in the Bay of Bengal.

(vi) There were several cyclones in the years 2016 (Roanu and Nada), 2020 (Nivar and Burevi), 2022 (Asani and Mandous) and 2025 (Montha and Ditwah). In 2025, exactly a month before Ditwah, (November 27, 2025) cyclone Montha affected the country’s eastern and northern parts (October 27) – a double whammy.

(vii) Climatologists interpret that Sri Lanka being an island in the Indian Ocean, the country is vulnerable to cyclones due to its position near the confluence of the Arabian Sea, the Bay of Bengal and the Indian Ocean.

(viii) The island registers increased cyclonic activity, especially in the period between October and December.

The need to re-determine the paddy cultivation seasons Yala and Maha vis-a-vis changing rainfall patterns

Sri Lanka had been faithfully following the rainfall patterns year in year out, in determining the Maha and Yala paddy cultivation seasons. The Maha season falls during the North-east monsoon from September to March in the following year. The Yala season is effective during the period from May to August. However, the current changes in the country’s rainfall pattern, would demand seriously reconsidering these seasons numerous cyclones had landed in the past few years, causing much damage to paddy as well as other cultivations. Cyclones Montha and Ditwah followed one after the other.

The need to be aware of the land we live in Our minds constantly give us a punch-list of things to fixate on. But we wouldn’t have ever thought about whether the environments we live in or do our businesses are hazardous, and therefore, that item should be etched in our punch-list. Ditwah has brought us immense sorrow and hardships. This unexpected onslaught has, therefore, driven home the truth that we need to be ever vigilant on the nature of the physical location we live in and carry on our activities. Japanese need not be told as to how they should act or react in an earthquake or a tsunami. Apart from cellphone-indications almost simultaneously their minds would revolve around magnitude of the earthquake and seismic intensity, tsunami, fires, electricity and power, public transportation, and what to do if you are inside a building or if you are outdoors.

A recent landslide caused by heavy rains accompanying Cyclone Ditwah

Against this backdrop it is really shocking to know of the experiences of both regional administrators and officials of the NBRO (National Building Research Organisation) in their attempts to persuade people to shift to safer locations, when deluges of cyclone Ditwah were expected to cause floods and earth slips/ landslides

Our most common and frequently occurring natural hazards

Apart from the Tsunami (December 26, 2004), that caused havoc in the Northeastern and Southern coastal belts in the country, our two most natural hazards that take a heavy toll on people’s lives and wellbeing, and cause immense damage to buildings, plantations, and critical infrastructure have been periodic floods and landslides. It has been reported that Ditwah has caused ‘an estimated $ 4.1 billion in direct physical damage to buildings, agriculture and critical infrastructure, which include roads, bridges, railway lines and communication links. It is further reported that total damage is equivalent to 4% of the country’s GDP.’

Floods and rain-induced landslides demand high alert and awareness

As the island is not placed within the ‘Ring of Fire’ where high seismic activity including earthquakes and volcanic activity is frequent, Sri Lanka’s notable hazards that occur almost perennially are floods and landslides; these calamities being consequent upon heavy rains falling during both the monsoonal periods, as well as the intermonsoonal periods where tropical revolving storms occur. When taking note of the new-normal rhythm of the country’s rainfall, those living in the already identified flood-basins would need to be ever vigilant, and conscious of emergency evacuation arrangements. Considering the numbers affected and distress caused by floods and disruptions to commercial activities, in the Western province, some have opined that priority would have been given to flood-prevention schemes in the Kelani river basin, over the Mahaweli multi-development programme.

Geomorphic processes carry on regardless, in reshaping the country’s geomorphological landscape

Geomorphic processes are natural mechanisms that eternally shape the earth’s surface. Although endogenic processes originating in the earth’s interior are beyond human control, exogenic processes occur continuously on or near the earth’s surface. These processes are driven by external forces, which mainly include:

(i) Weathering: rock-disintegration through physical, chemical and biological processes, resulting in soil and sediment formation.

(ii) Erosion: Dislocation/ removal and movement of weathered materials by water and wind (as ice doesn’t play a significant role in the Tropics).

(iii) Transportation: The shifting of weathered material to different locations often by rivers, wind, heavy rains,

(iv) Deposition: Transported material being settled forming new landforms, lowering of hills, and flattening of undulated land or depositing in the seabed.

What we witnessed during heavy rains caused by cyclone Ditwah is the above process, what geomorphologists refer to as ‘denudation’. This process is liable to accelerate during spells of heavy rain, causing landslides, landfalls, earth and rock slips/ rockslides and landslides along fault lines.

Hence, denudation is quite a natural phenomenon, the only deviation being that it gets quickened during heavy rains when gravitational and other stresses within a slope exceed the shear strength of the material that forms slopes.

It is, therefore, a must that both people and relevant authorities should be conscious of the consequences, as Ditwah was not the first cyclone that hit the country. Cyclone Roanu in May 2016 caused havoc by way of landslides, Aranayake being an area severely affected.

Conscious data-studies and analyses and preparedness; Two initials to minimise potential dangers

Sri Lanka has been repeatedly experiencing heavy rain–related disasters as the table of cyclones clearly shows (numbering 22 cyclones within the last 60 years). Further, Sri Lanka possesses comprehensive hazard profiles developed to identify and mitigate risks associated with these natural hazards.

A report of the Department of Civil Engineering, University of Moratuwa, says “Rain induced landslides occur in 13 major districts in the central highland and south western parts of the country which occupies about 20-30% of the total land area, and affects 30-38% of total population (6-7.6 Million). The increase of the number of landslides and the affected areas over the years could be attributed to adverse changes in the land use pattern, non-engineered constructions, neglect of maintenance and changes in the climate pattern causing high intensity rainfalls.”

ENVIRONMENTAL LITERACY

Environmental awareness being simply knowing facts will be of no use unless such knowledge is coupled with environmental literacy. Promoting environmental literacy is crucial for meeting environmental challenges and fostering sustainable development. In this context literacy involves understanding ecological principles and environmental issues, as well as the skills and techniques needed to make informed decisions for a sustainable future. This aspect is the most essential component in any result-oriented system to mitigate periodic climate-related hazards.

Environmental literacy rests upon several crucial pillars

The more important pillars among others being:

· Data-based comprehensive knowledge of problems and potential solutions

· Skills to analyse relevant data and information critically, and communicate effectively the revelations to relevant agencies promptly and accurately.

· Identification and Proper interconnectedness among relevant agencies

· Disposition – The attitudes, values and motivation that drive responsible environmental behaviour and engagement.

· Action – The required legal framework and the capacity to effectively translate knowledge, skills and disposition into solid action that benefits the environment.

· Constant sharing of knowledge with relevant international bodies on the latest methods adopted to harmonise human and physical environments.

· Education programmes – integrating environmental education into formal curricula and equipping students with a comprehensive understanding of ecosystems and resource management. Re-structuring the geography syllabus, giving adequate emphasis to environmental issues and changing patterns of weather and overall climate, would seem a priority act.

· Experiential learning – Organising and engaging in field studies and community projects to gain practical insights into environmental conservation.

· Establishing area-wise warning systems, similar to Tsunami warning systems.

· Interdisciplinary Approaches to encourage students to relate ecological knowledge with such disciplines as geology, geography, economics and sociology.

· Establishing Global Collaboration – Leveraging technology and digital platforms to expand access to environmental education and enhance awareness on global environmental issues.

· Educating the farming community especially on the changes occurring in weather and climate.

· Circumventing high and short duration rainfall extremes by modifying cultivation patterns, and introducing high yielding short-duration yielding varieties, including paddy.

· Soil management that reduces soil erosion

· Eradicating misconceptions that environmental literacy is only for scientists (geologists), environmental professionals and relevant state agencies.

A few noteworthy facts about the ongoing climatic changes

1. The year 2025 was marked by one of the hottest years on record, with global

temperatures surpassing 1.5ºC.

2. Russia has been warming at more than twice the global average since 1976, with 2024 marking the hottest year ever recorded.

3. Snowfalls in the Sahara – a rare phenomenon, with notable occurrences recorded in recent years.

4. Monsoon rains in the Indian Subcontinent causing significant flooding and landslides

5. Warming of the Bay of Bengal, intensifying weather activity.

6. The Himalayan region, which includes India, Nepal, Pakistan, and parts of China, experiencing temperatures climbing up to 2ºC above normal, along with widespread above-average rainfall.

7. Sri Lanka experienced rainfall exceeding 300 m.m. in a single day, an unprecedented occurrence in the island’s history. Gammaduwa, in Matale, received 540 m.m. of rainfall on a day, when Ditwah rainfall was at its peak.

The writer could be contacted at kalyanaratnekai@gmail.com

by K. A. I. KALYANARATNE ✍️
Former Management Consultant /
Senior Manager, Publications
Postgraduate Institute of Management,
University of Sri Jayewardenepura,
Vice President, Hela Hawula

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