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Dams indispensable but not without adverse impacts

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By Eng. Thushara Dissanayake

Human civilization began along rivers in the world over, as water is an essential natural resource for people. These early river valley civilizations include the Indus valley, the ancient Egypt near the Nile river, the Mesopotamia civilization along the Tigris and Euphrates rivers, and the Chinese civilization along the Yellow river. Later on, with the increase in population and technological advancements thousands of dams have been built to meet the water needs during dry periods by regulating river flows.

Today, according to estimates there are 59,071 large dams all over the world with a total storage of 16,201 Km3 according to registered data of International Commission on Large Dams (ICOLD). A dam is categorised as large if the height is greater than 15m. A dam of height 5-15 m is also considered as a large dam if its storage capacity is more than 3 MCM. Accordingly, Sri Lanka has around 80 large dams, 270 medium dams and over 10,000 small dams.

Dam types concrete, earthen, rockfill and masonry. This marvelous engineering innovation has been very useful to humanity as it provides a wide range of social, environmental and economic benefits. Providing water for domestic use, agriculture, hydropower generation, and flood mitigation are some of the main functions of dams. However, these manmade structures are not without significant impact on the environment and society. Knowing these impacts are useful in mitigating them for the ecological sustainability and social wellbeing of a country. Although the impacts of large dams are studied extensively, those of small dams are often neglected. Following are some major and quantifiable impacts of dams.

 

Siltation behind the dam

A dam greatly alters the morphological processes of rivers and streams crossed by the dam. River water naturally transport the soil eroded in the upper watersheds by rain as sediment materials up to sea. When a dam is built across a river this sediment transportation process is completely blocked. This makes the river section downstream to the reservoir sediment-hungry and river bed erosion is the result. Thus, deepened river bed cause the ground water table to decrease. The result is either a decrease in water availability or a complete drying up of nearby domestic or agro wells. These issues are further exacerbated by sand mining in rivers.

The formation of meandering river sections and oxbow lakes occur downstream many large dams in Sri Lanka due to lack of downstream sediment transport. In low lying agricultural areas, this change of river course has become a worrying issue for land owners. Further, bridge foundations in the river are exposed due to bed erosion threatening their stability. On the other hand, deficiency in sediment transport to the sea causes beaches to vanish and result in coastal erosion.

 

Increased flood risks

Most of the time reservoirs are considered flood mitigation structures. However, during continuous rains the emergency flood gates of the reservoirs are opened for their own safety. If the downstream part of the reservoir is also receiving high rainfalls the opening of flood gates would create excessive floods due to above – normal – flow capacity in the river endangering people and property in a far worse manner.

 

Reduction of downstream river flow

Reduced river flows increase the salinity level of river water closer to coastal areas impacting drinking water extractions. This has to be overcome by the construction of costly structures such as salinity barriers across rivers. The salinity intrusion can also contaminate ground water aquifers.

Dams regulate flood waters and as a consequence flood plain characteristics are altered. Generally, the soil eroded by the rain is the topmost soil layer of the river’s watershed and it is rich in nutrients. Hence, floodplains will be deprived of such nutrients as long as floodplains are not inundated by flood waters affecting agricultural activities carried out in flood plain areas. The lack of nutrient rich riverine sediments alters the ecologies of river deltas, estuaries, coastal wetlands and marine environments as well.

Block of passage for migratory animals

Migratory animals, especially fish travel along the river to upstream areas for breeding. On the other hand, the species in the food chain that depend on these migratory animals are negatively impacted when their passage is blocked by a dam.

 

Land inundation

With the construction of a dam a large area is inundated. For instance, the inundation area due to the construction of Senanayake Samudra, the largest reservoir in Sri Lanka by volume, is around 7,689 hectares. Not only bare lands, sometimes, inundation of townships, wetlands, forest and agriculture areas are also possible if permitted by proper environmental assessment processes.

 

Production of greenhouse gases

Today, the world is gravely concerned about climate change, which is known to be a consequence of global warming due to increasing greenhouse gases in the atmosphere. Often, carbon dioxide emissions from the combustion of fossil fuels are considered the major contributors for global warming. Yet, reservoirs also contribute to greenhouse gas emissions by releasing methane which is a high potential greenhouse gas. Methane is produced in reservoir beds from the decomposition of the plant materials primarily inundated after the reservoir construction.

 

Social Impacts

Dams have caused displacement of a huge number of people around the world as an adverse impact due to inundation of public properties. Most of the major dams in Sri Lanka were constructed many decades ago without facing any severe resettlement issues, whereas future dam construction works would not be so, due to urbanisation and increased population density. Further, dam construction has resulted in conflicts of water sharing specially in transboundary river basins. Being a small country, Sri Lanka is fortunate not to have such conflicts except for the Mahaweli Ganga, where minor conflicts are on the verge with ongoing developments. Loss of cultural heritage assets is another issue which could be more sensitive to people.

 

Dam failure risks

If a dam failed, it would be a huge disaster to people living close by and their properties. Dam failures could occur due to myriad reasons. Overtopping, piping, slope stability and settlement are the common modes of failure, though at times, exact reason is unknown.

In January 1986, Sri Lanka experienced the breach of the Kantalai dam in the Eastern Province. The disaster resulted in 127 deaths and affected 10,864 residents. The number of houses destroyed was 1,200, besides significant damage to agriculture and infrastructure in the area. Apart from that, massive floods in December 1957 caused failure of 35 large dams, 53 medium dams and 1500 small dams in the country within few days. The Banqiao dam failure of China, in 1975, is considered to be the deadliest of its kind ever. It destroyed 171,000 lives and displaced millions of people.

 

Final remarks

It is not wise to assume that all engineering innovations are sound and safe. The way science and technology evolved throughout the history of mankind has posed many threats to the sustainability of the world. Hence, enhancing the positive impacts of such technological creations and taking action to mitigate the negative impacts to the best possible level are the responsibilities of those who are involved in these endeavours.

(The writer is a chartered Civil Engineer. He can be reached through dmtsdissa@yahoo.com)

 

 

 

 

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Islamophobia and the threat to democratic development

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There’s an ill more dangerous and pervasive than the Coronavirus that’s currently sweeping Sri Lanka. That is the fear to express one’s convictions. Across the public sector of the country in particular many persons holding high office are stringently regulating and controlling the voices of their consciences and this bodes ill for all and the country.

The corrupting impact of fear was discussed in this column a couple of weeks ago when dealing with the military coup in Myanmar. It stands to the enduring credit of ousted Myanmarese Head of Government Aung San Suu Kyi that she, perhaps for the first time in the history of modern political thought, singled out fear, and not power, as the principal cause of corruption within the individual; powerful or otherwise.

To be sure, power corrupts but the corrupting impact of fear is graver and more devastating. For instance, the fear in a person holding ministerial office or in a senior public sector official, that he would lose position and power as a result of speaking out his convictions and sincere beliefs on matters of the first importance, would lead to a country’s ills going unaddressed and uncorrected.

Besides, the individual concerned would be devaluing himself in the eyes of all irrevocably and revealing himself to be a person who would be willing to compromise his moral integrity for petty worldly gain or a ‘mess of pottage’. This happens all the while in Lankan public life. Some of those who have wielded and are wielding immense power in Sri Lanka leave very much to be desired from these standards.

It could be said that fear has prevented Sri Lanka from growing in every vital respect over the decades and has earned for itself the notoriety of being a directionless country.

All these ills and more are contained in the current controversy in Sri Lanka over the disposal of the bodies of Covid victims, for example. The Sri Lankan polity has no choice but to abide by scientific advice on this question. Since authorities of the standing of even the WHO have declared that the burial of the bodies of those dying of Covid could not prove to be injurious to the wider public, the Sri Lankan health authorities could go ahead and sanction the burying of the bodies concerned. What’s preventing the local authorities from taking this course since they claim to be on the side of science? Who or what are they fearing? This is the issue that’s crying out to be probed and answered.

Considering the need for absolute truthfulness and honesty on the part of all relevant persons and quarters in matters such as these, the latter have no choice but to resign from their positions if they are prevented from following the dictates of their consciences. If they are firmly convinced that burials could bring no harm, they are obliged to take up the position that burials should be allowed.

If any ‘higher authority’ is preventing them from allowing burials, our ministers and officials are conscience-bound to renounce their positions in protest, rather than behave compromisingly and engage in ‘double think’ and ‘double talk’. By adopting the latter course they are helping none but keeping the country in a state of chronic uncertainty, which is a handy recipe for social instabiliy and division.

In the Sri Lankan context, the failure on the part of the quarters that matter to follow scientific advice on the burials question could result in the aggravation of Islamophobia, or hatred of the practitioners of Islam, in the country. Sri Lanka could do without this latter phobia and hatred on account of its implications for national stability and development. The 30 year war against separatist forces was all about the prevention by military means of ‘nation-breaking’. The disastrous results for Sri Lanka from this war are continuing to weigh it down and are part of the international offensive against Sri Lanka in the UNHCR.

However, Islamophobia is an almost world wide phenomenon. It was greatly strengthened during Donald Trump’s presidential tenure in the US. While in office Trump resorted to the divisive ruling strategy of quite a few populist authoritarian rulers of the South. Essentially, the manoeuvre is to divide and rule by pandering to the racial prejudices of majority communities.

It has happened continually in Sri Lanka. In the initial post-independence years and for several decades after, it was a case of some populist politicians of the South whipping-up anti-Tamil sentiments. Some Tamil politicians did likewise in respect of the majority community. No doubt, both such quarters have done Sri Lanka immeasurable harm. By failing to follow scientific advice on the burial question and by not doing what is right, Sri Lanka’s current authorities are opening themselves to the charge that they are pandering to religious extremists among the majority community.

The murderous, destructive course of action adopted by some extremist sections among Muslim communities world wide, including of course Sri Lanka, has not earned the condemnation it deserves from moderate Muslims who make-up the preponderant majority in the Muslim community. It is up to moderate opinion in the latter collectivity to come out more strongly and persuasively against religious extremists in their midst. It will prove to have a cementing and unifying impact among communities.

It is not sufficiently appreciated by governments in the global South in particular that by voicing for religious and racial unity and by working consistently towards it, they would be strengthening democratic development, which is an essential condition for a country’s growth in all senses.

A ‘divided house’ is doomed to fall; this is the lesson of history. ‘National security’ cannot be had without human security and peaceful living among communities is central to the latter. There cannot be any ‘double talk’ or ‘politically correct’ opinions on this question. Truth and falsehood are the only valid categories of thought and speech.

Those in authority everywhere claiming to be democratic need to adopt a scientific outlook on this issue as well. Studies conducted on plural societies in South Asia, for example, reveal that the promotion of friendly, cordial ties among communities invariably brings about healing among estranged groups and produces social peace. This is the truth that is waiting to be acted upon.

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Pakistan’s love of Sri Lanka

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By Sanjeewa Jayaweera

It was on 3rd January 1972 that our family arrived in Karachi from Moscow. Our departure from Moscow had been delayed for a few weeks due to the military confrontation between Pakistan and India. It ended on 16th December 1971. After that, international flights were not permitted for some time.

The contrast between Moscow and Karachi was unbelievable. First and foremost, Moscow’s temperature was near minus 40 degrees centigrade, while in Karachi, it was sunny and a warm 28 degrees centigrade. However, what struck us most was the extreme warmth with which the airport authorities greeted our family. As my father was a diplomat, we were quickly ushered to the airport’s VIP Lounge. We were in transit on our way to Rawalpindi, the airport serving the capital of Islamabad.

We quickly realized that the word “we are from Sri Lanka” opened all doors just as saying “open sesame” gained entry to Aladdin’s cave! The broad smile, extreme courtesy, and genuine warmth we received from the Pakistani people were unbelievable.

This was all to do with Mrs Sirima Bandaranaike’s decision to allow Pakistani aircraft to land in Colombo to refuel on the way to Dhaka in East Pakistan during the military confrontation between Pakistan and India. It was a brave decision by Mrs Bandaranaike (Mrs B), and the successive governments and Sri Lanka people are still enjoying the fruits of it. Pakistan has been a steadfast and loyal supporter of our country. They have come to our assistance time and again in times of great need when many have turned their back on us. They have indeed been an “all-weather” friend of our country.

Getting back to 1972, I was an early beneficiary of Pakistani people’s love for Sri Lankans. I failed the entrance exam to gain entry to the only English medium school in Islamabad! However, when I met the Principal, along with my father, he said, “Sanjeewa, although you failed the entrance exam, I will this time make an exception as Sri Lankans are our dear friends.” After that, the joke around the family dinner table was that I owed my education in Pakistan to Mrs B!

At school, my brother and I were extended a warm welcome and always greeted “our good friends from Sri Lanka.” I felt when playing cricket for our college; our runs were cheered more loudly than of others.

One particular incident that I remember well was when the Embassy received a telex from the Foreign inistry. It requested that our High Commissioner seek an immediate meeting with the Prime Minister of Pakistan, Mr Zulifikar Ali Bhutto (ZB), and convey a message from Mrs B. The message requested that an urgent shipment of rice be dispatched to Sri Lanka as there would be an imminent rice shortage. As the Ambassador was not in the station, the responsibility devolved on my father.

It usually takes about a week or more to get an audience with the Prime Minister (PM) of a foreign country due to their busy schedule. However, given the urgency, my father spoke to the Foreign Ministry’s Permanent Sectary, who fortunately was our neighbour and sought an urgent appointment. My father received a call from the PM’s secretary around 10 P.M asking him to come over to the PM’s residence. My father met ZB around midnight. ZB was about to retire to bed and, as such, was in his pyjamas and gown enjoying a cigar! He had greeted my father and had asked, “Mr Jayaweera, what can we do for great friend Madam Bandaranaike?. My father conveyed the message from Colombo and quietly mentioned that there would be riots in the country if there is no rice!

ZB had immediately got the Food Commissioner of Pakistan on the line and said, “I want a shipload of rice to be in Colombo within the next 72 hours!” The Food Commissioner reverted within a few minutes, saying that nothing was available and the last export shipment had left the port only a few hours ago to another country. ZB had instructed to turn the ship around and send it to Colombo. This despite protests from the Food Commissioner about terms and conditions of the Letter of Credit prohibiting non-delivery. Sri Lanka got its delivery of rice!

The next was the visit of Mrs B to Pakistan. On arrival in Rawalpindi airport, she was given a hero’s welcome, which Pakistan had previously only offered to President Gaddafi of Libya, who financially backed Pakistan with his oil money. That day, I missed school and accompanied my parents to the airport. On our way, we witnessed thousands of people had gathered by the roadside to welcome Mrs B.

When we walked to the airport’s tarmac, thousands of people were standing in temporary stands waving Sri Lanka and Pakistan flags and chanting “Sri Lanka Pakistan Zindabad.” The noise emanating from the crowd was as loud and passionate as the cheering that the Pakistani cricket team received during a test match. It was electric!

I believe she was only the second head of state given the privilege of addressing both assemblies of Parliament. The other being Gaddafi. There was genuine affection from Mrs B amongst the people of Pakistan.

I always remember the indefatigable efforts of Mr Abdul Haffez Kardar, a cabinet minister and the President of the Pakistan Cricket Board. From around 1973 onwards, he passionately championed Sri Lanka’s cause to be admitted as a full member of the International Cricket Council (ICC) and granted test status. Every year, he would propose at the ICC’s annual meeting, but England and Australia’s veto kept us out until 1981.

I always felt that our Cricket Board made a mistake by not inviting Pakistan to play our inaugural test match. We should have appreciated Mr Kardar and Pakistan’s efforts. In 1974 the Pakistan board invited our team for a tour involving three test matches and a few first-class games. Most of those who played in our first test match was part of that tour, and no doubt gained significant exposure playing against a highly talented Pakistani team.

Several Pakistani greats were part of the Pakistan and India team that played a match soon after the Central Bank bomb in Colombo to prove that it was safe to play cricket in Colombo. It was a magnificent gesture by both Pakistan and India. Our greatest cricket triumph was in Pakistan when we won the World Cup in 1996. I am sure the players and those who watched the match on TV will remember the passionate support our team received that night from the Pakistani crowd. It was like playing at home!

I also recall reading about how the Pakistani government air freighted several Multi Barrell artillery guns and ammunition to Sri Lanka when the A rmy camp in Jaffna was under severe threat from the LTTE. This was even more important than the shipload of rice that ZB sent. This was crucial as most other countries refused to sell arms to our country during the war.

Time and again, Pakistan has steadfastly supported our country’s cause at the UNHCR. No doubt this year, too, their diplomats will work tirelessly to assist our country.

We extend a warm welcome to Mr Imran Khan, the Prime Minister of Pakistan. He is a truly inspirational individual who was undoubtedly an excellent cricketer. Since retirement from cricket, he has decided to get involved in politics, and after several years of patiently building up his support base, he won the last parliamentary elections. I hope that just as much as he galvanized Sri Lankan cricketers, his political journey would act as a catalyst for people like Kumar Sangakkara and Mahela Jayawardene to get involved in politics. Cricket has been called a “gentleman’s game.” Whilst politics is far from it!.

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Covid-19 health rules disregarded at entertainment venues?

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Believe me, seeing certain videos, on social media, depicting action, on the dance floor, at some of these entertainment venues, got me wondering whether this Coronavirus pandemic is REAL!

To those having a good time, at these particular venues, and, I guess, the management, as well, what the world is experiencing now doesn’t seem to be their concerned.

Obviously, such irresponsible behaviour could create more problems for those who are battling to halt the spread of Covid-19, and the new viriant of Covid, in our part of the world.

The videos, on display, on social media, show certain venues, packed to capacity – with hardly anyone wearing a mask, and social distancing…only a dream..

How can one think of social distancing while gyrating, on a dance floor, that is over crowded!

If this trend continues, it wouldn’t be a surprise if Coronavirus makes its presence felt…at such venues.

And, then, what happens to the entertainment scene, and those involved in this field, especially the musicians? No work, whatsoever!

Lots of countries have closed nightclubs, and venues, where people gather, in order to curtail the spread of this deadly virus that has already claimed the lives of thousands.

Thailand did it and the country is still having lots of restrictions, where entertainment is concerned, and that is probably the reason why Thailand has been able to control the spread of the Coronavirus.

With a population of over 69 million, they have had (so far), a little over 25,000 cases, and 83 deaths, while we, with a population of around 21 million, have over 80,000 cases, and more than 450 deaths.

I’m not saying we should do away with entertainment – totally – but we need to follow a format, connected with the ‘new normal,’ where masks and social distancing are mandatory requirements at these venues. And, dancing, I believe, should be banned, at least temporarily, as one can’t maintain the required social distance, while on the dance floor, especially after drinks.

Police spokesman DIG Ajith Rohana keeps emphasising, on TV, radio, and in the newspapers, the need to adhere to the health regulations, now in force, and that those who fail to do so would be penalised.

He has also stated that plainclothes officers would move around to apprehend such offenders.

Perhaps, he should instruct his officers to pay surprise visits to some of these entertainment venues.

He would certainly have more than a bus load of offenders to be whisked off for PCR/Rapid Antigen tests!

I need to quote what Dr. H.T. Wickremasinghe said in his article, published in The Island of Tuesday, February 16th, 2021:

“…let me conclude, while emphasising the need to continue our general public health measures, such as wearing masks, social distancing, and avoiding crowded gatherings, to reduce the risk of contact with an infected person.

“There is no science to beat common sense.”

But…do some of our folks have this thing called COMMON SENSE!

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