Within the essay “Who’s liable for Sikkim’s glacial lake outburst flood?” that appeared in Frontline on October 25, 2023, the creator and researcher Mona Chettri wrote: “On the evening of October 3, 2023, the South Lhonak Lake in North Sikkim breached, inflicting a Glacial Lake Outburst Flood (GLOF).
“Positioned roughly 60 kilometres downstream of the lake, in Chungthang city of Mangan district, was the 1,200 MW Teesta III dam, the most important hydropower mission in Sikkim. The dam was decimated by the GLOF, which additionally unleashed devastation on downstream areas and communities.”
A catastrophe of this magnitude within the fragile ecosystem of the Himalaya had lengthy been predicted. However the curiosity in hydropower—categorised as inexperienced power regardless of its terribly poor document in that respect—continues unabated. R.Okay. Singh, the then Union Minister for Energy, and New & Renewable Vitality, acknowledged in a written reply within the Rajya Sabha on December 12, 2023, that eight massive hydropower initiatives (above 25 megawatt), with a mixed capability of 6,037 MW, had been beneath development within the north-eastern area; one in all these initiatives is the two,000 MW Decrease Subansiri dam, one of many largest hydropower initiatives deliberate within the Himalayan area, which is prone to develop into operational quickly, after years of delay, quite a few accidents on web site, and value escalations. Delays, disasters, and devolvement are the norm moderately than the exception in most such initiatives deliberate throughout India. But extra are on the anvil as clearances get issued.
The Himalayan plate boundary exhibiting the most important earthquakes in current historical past (1897 to 1950). The Central Seismic Hole is the section that has not been affected by any nice earthquakes over the last a number of centuries. In keeping with analysis scientists on the College of Colorado, Boulder, this means that the area is overdue for an earthquake with a magnitude of 8.
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From The Rumbling Earth: The Story of Indian Earthquakes by C.P. Rajendran and Kusala Rajendran
As an example, in Arunachal Pradesh, on August 12, 2023, the State authorities handed over to a few Central public sector undertakings 12 long-pending hydropower initiatives that the personal sector had taken on after which rejected as unviable. All of the initiatives come at terribly excessive price—financially, socially, and ecologically. As an example, the projected price overrun of the Decrease Subansiri dam is predicted to be over Rs.13,200 crore, whereas ecological prices contain the destruction of swathes of evergreen forests, and social prices embrace the displacement of individuals with out ample compensation or resettlement provisions. Resentment in opposition to these initiatives has been brewing for a very long time in Arunachal Pradesh, with human rights teams and organisations pleading to let affected individuals have a larger say within the decision-making course of. Their objections have gone largely unheeded.
Dangers of massive initiatives
The large query then is, are initiatives of this magnitude price it? The reply includes not simply cost-benefit analyses and understanding of the current dismal historical past of the hydropower sector however one other important ingredient: danger. Hydropower initiatives within the Himalaya face two actual, ever-present, dangers: the potential of a devastating earthquake and ruinous floods attributable to glacial lake overflows.
In April 2015, an earthquake in Nepal with a second magnitude (Mw) of seven.8 killed over 9,000 individuals and injured no less than 22,000; it was the worst pure catastrophe in Nepal for the reason that 1934 Nepal-Bihar earthquake. It triggered an avalanche on Mount Everest, killing 22 climbers and flattening villages, decimating a 3rd of Nepal’s hydropower capability and destroying UNESCO World Heritage Websites within the Kathmandu valley. This got here shut on the heels of the Uttarakhand floods of 2013, probably attributable to a glacial lake outburst, which killed a whole bunch and broken properties price crores in India, together with no less than 10 hydropower initiatives beneath development.
A person stands on the rubble of homes broken within the 2015 earthquake in Bhaktapur, Nepal. April 6, 2016.
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NIRANJAN SHRESTHA/ AP
Earthquakes are prone to recur within the Himalaya: scientific research have warned of a devastating, intense earthquake with a Mw of above 8 within the area. Internationally, one nice earthquake—outlined as an occasion that measures 8 or extra on the Mw scale—occurs yearly or two. Knowledge assist us perceive the harmful potential of such an earthquake: an earthquake with a magnitude of 8 has 10 instances the extent of floor shaking as an earthquake with a magnitude 7 and releases power equal to that ensuing from the detonation of 6 million tonnes of TNT.
In an article in The Hindu titled “A hydro onslaught the Himalayas can’t take” (September 3, 2021), Mallika Bhanot, a member of Ganga Ahvaan, and C.P. Rajendran, Adjunct Professor, Nationwide Institute of Superior Research, word that about 15 per cent of the nice earthquakes of the twentieth century befell within the Himalaya.
Chance of a terrific earthquake
The probability of such an earthquake recurring within the Himalaya has been endorsed by various specialists, together with Roger Bilham, Professor of Geology, College of Colorado at Boulder, and Luca Dal Zilio, Assistant Professor of Geophysics, Earth Observatory of Singapore. In August 2020, Steven G. Wesnousky, Professor of Geology and Seismology, College of Nevada, US, printed a paper within the analysis journal Seismological Analysis Letters titled “Nice Pending Himalayan Earthquakes”. The principal conclusion of his paper was that geological, historic, and geophysical observations present that the complete Himalayan arc is poised to supply a sequence of nice earthquakes. Supriyo Mitra, Professor on the Division of Earth Sciences within the Indian Institute of Science Training and Analysis, Kolkata, famous that this analysis matched earlier research.
Highlights
- Regardless of repeated pure disasters within the Himalaya, the curiosity in hydropower—categorised as inexperienced power regardless of its terribly poor document in that respect—continues unabated
- Scientific research have warned of a devastating, intense earthquake with a Mw of above 8 within the area
- It should have horrific penalties for communities dwelling alongside these buildings and downstream from them, with financial losses working into billions of {dollars} and environmental harm that can take a long time to restore
The eminence of those scientists and their observations have to be taken critically. Arunachal Pradesh is categorised as Zone V (at most danger) within the mapping of seismic zones in India and it has a current historical past of quite a few quakes measuring above 5 on the Richter scale, together with the Assam-Tibet earthquake of 1950 with its epicentre within the Mishmi Hills that killed no less than 4,800 individuals.
The flash flood-ravaged city of Rangpo in Sikkim, on October 5, 2023. The flooding was worsened when components of a dam on the Teesta had been washed away.
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Prakash Adhikari/ AP
The important distinction between the nice earthquakes of half a century in the past and people of as we speak is that the damaging influence of such an earthquake on a mega-structure like a dam might be with out priority. It should have horrific penalties for communities dwelling alongside these buildings and downstream from them, with financial losses working into billions of {dollars} and environmental harm that can take a long time to restore (if in any respect). The harm to the mountain ecosystem might be immeasurable, making it much more susceptible to future hazards. Compounding the chance is the rising menace from glacial lake outbursts because of local weather change.
A person stands on the banks of the swollen Satluj after heavy monsoon rains in Rampur, Himachal Pradesh, on July 9, 2023.
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AFP
Satellite tv for pc imagery and ground-level observations point out that glaciers within the Himalaya are melting at an unprecedented fee, rising the probabilities of glacial lake breaches or “outbursts”. GLOFs have already induced large-scale destruction: the Uttarakhand floods of 2013, for example, which induced immense harm, had been triggered by very heavy rainfall together with local weather change-induced melting of the Chorabari glacier. As local weather change gathers higher-than-expected momentum, the variety of glacial lakes being created (they’re shaped in massive depressions that had been earlier eroded by glacial exercise) and the concomitant dangers posed by GLOFs are compounding.
Additionally Learn | Why massive dams spell doom for Arunachal Pradesh
Within the Chenab basin, for example, the place Lahaul is located, the specter of such outbursts looms massive: from simply 55 such lakes in 2001, the basin recorded 254 in 2018, a rise of 462 per cent in simply 18 years. A analysis paper titled “Hazard from Himalayan glacier lake outburst floods” (2019) by Georg Veh, Oliver Korup, and Ariane Walz famous with concern: “Sustained glacier soften within the Himalayas has progressively spawned greater than 5,000 glacier lakes which might be dammed by doubtlessly unstable moraines. When such dams break, glacier lake outburst floods could cause catastrophic societal and geomorphic impacts.”
Menace of flash floods
In April 2024, the Indian Area Analysis Organisation (ISRO) launched satellite-data-based evaluation overlaying about 40 years on enlargement of glacial lakes within the catchment areas of Indian Himalayan rivers. A catchment is an unlimited space of land often surrounded by hills or mountains that collects water, which, in flip, is funnelled into the river by means of streams and underground channels. The ISRO research was meant to know the modifications which have occurred, principally as a consequence of local weather change. The outcomes had been worrying: 1 / 4 of those lakes have expanded to about twice their dimension from 4 a long time in the past as glaciers retreat within the face of warming.
One other research from July 2016 led by Wolfgang Schwanghart, a geomorphologist on the Institute of Earth and Environmental Sciences, College of Potsdam, Germany, estimated that of the 177 hydropower initiatives situated near Himalayan glaciers, over a fifth—together with many in India—could possibly be beneath menace from floods attributable to glacial lake outbursts. Worryingly, a lot of these hydro initiatives are situated within the jap Himalaya, the place the GLOF dangers are the very best (the ISRO research estimated that 58 lakes within the catchment of the Brahmaputra have expanded considerably).
Scientific and visible proof
If earthquakes and GLOFs weren’t sufficient, there’s one other danger: of random raining of particles from the comparatively younger Himalayan land-mass, which is now being modified at an unprecedented fee. The European Area Company reported on June 14, 2021, “On 7 February 2021, the Chamoli district within the Uttarakhand area of India skilled a humanitarian tragedy when a big mass of rock and ice, round 27 million cubic metres, was launched from the steep mountain flank of the Ronti peak.
Muck deposited on the banks of the Alaknanda river in the course of the restore and restoration of Vishnuprayag hydropower mission’s barrage on December 6, 2013.
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KAVITA UPADHYAY
This collapse induced a movement of particles to barrel down the Ronti Gad, Rishiganga, and Dhauliganga river valleys, inflicting important destruction alongside the route, killing greater than 200 individuals and destroying two main hydropower services that had been beneath development…. The research supplies satellite tv for pc proof that the catastrophe was attributable to a big mass of ice and rock dislodged from the slopes of Ronti Peak, beginning as a large landslide that reworked right into a mud and particles movement inflicting destruction alongside its path.” The BBC reported: “To place this quantity [of debris] in context, it’s about 10 instances that of the Nice Pyramid of Giza in Egypt. When the mass hit the Ronti Gad valley ground, it launched the power equal to fifteen Hiroshima atomic bombs” (“Chamoli catastrophe: ‘It hit the valley ground like 15 atomic bombs’”, June 13, 2021).
Additionally Learn | Who’s liable for Sikkim’s glacial lake outburst flood?
The egregious and reckless development exercise in these fragile ecosystems—each public constructions comparable to for roads and hydropower dams and personal housing—is making the issue worse. Landslides are much more frequent as we speak than they was once, extra so alongside slopes which have witnessed development.
The 2023 monsoon season was disastrous for Himachal Pradesh. The Environics Belief reported: “Unprecedented rains in the course of the present monsoon season in a number of pockets have wreaked havoc throughout the State. Excessive occasions comparable to flash floods and cloudbursts and related landslides, subsidence and sinking of land and full failure of populated hill slopes devastated lives throughout the State. Present estimates point out 404 individuals misplaced their lives, 38 individuals are nonetheless lacking, and 377 have been injured within the numerous occasions throughout the State.… Three excessive spells [emphasis added] (8 to 11 July, 14 to fifteen August, and 22 to 23 August) and 163 recognized landslides and 72 flash floods have been liable for many of the influence. Kullu, Mandi, Shimla, Sirmaur, Solan and Chamba districts had been among the worst affected” (“Preliminary evaluation of 2023 catastrophe throughout Himachal Pradesh”, September 2023).
There’s sufficient scientific and visible proof as we speak to rethink the aggressive plan for Himalayan growth and undertake the precautionary precept, one which acts earlier than there’s full scientific proof of a danger. There’s far an excessive amount of at stake to proceed down the present course, and in our humility lies redemption.
Gopakumar Menon is a conservationist and creator with a deep curiosity within the Himalaya.
