On the night of October 3, 2023, the South Lhonak Lake in North Sikkim breached, causing a Glacial Lake Outburst Flood (GLOF). Located approximately 60 kilometres downstream of the lake, in Chungthang town of Mangan district, was the 1,200 MW Teesta III dam, the biggest hydropower project in Sikkim. The dam was decimated by the GLOF, which also unleashed devastation on downstream areas and communities. According to a preliminary assessment report by Sphere India, 88,400 people have been directly affected—40 lives lost, 76 still missing—and 33 bridges, two government buildings, and 16 roads and highways have been damaged.
Chungthang is a small town on the confluence of the Lachen chu (river) and Lachung chu, which form the Teesta. It is a gateway to tourist destinations further north, and an important forward base of the Indian Army. The Teesta III dam, which started functioning in 2017, was developed by Teesta Urja Limited at the cost of Rs.13,965 crore; the majority share is now owned by the Government of Sikkim.
Teesta III is part of a cascade network of dams in the Teesta basin with a combined installed capacity of 4,694 MW. To date, only a few of these projects have been commissioned (the 110 MW Chujachen HEP, 96 MW Jorethang Loop, 96MW Dikchu HEP, 97 MW Tashiding HEP and the 510 MV Teesta V). Others have been scrapped, have changed hands between developers or have been delayed. All the dams on the Teesta and its tributaries are run-of-the river systems (which entail guiding the flowing waters of a river through a canal or penstock to spin a turbine and so, generate electricity).
When I visited the Teesta III dam site in 2017, it was close to being commissioned. The sheer size of the reservoir dominated the physical landscape of Chungthang, inspiring both awe at the engineering feat, and fear for what might happen if anything were to go wrong. On the night of October 3, the South Lhonak GLOF drained an area of about 105 hectares. From an altitude of 5,200 metres, the flood water made its way down the mountains with great velocity, reaching the dam site in just over an hour.
The reservoir of the Chungthang dam was full, holding approximately 5 million cubic metres (mcm) of water. Within 10 minutes, the dam gave way, wreaking havoc on Chungthang town. Approximately 80 eighty per cent of the town sustained severe damage; the Indian Army’s forward base stationed there also suffered serious damage to property and loss of explosives and ammunition (some of which detonated on riverbanks, killing and injuring people).
Further downstream, the floodwater damaged the power station and bridge of the 510 MW Teesta V. Bolstered by the reservoir water, the water rushed down the hills, scouring the sides of hills and valleys, triggering landslides—a raging wall of water, silt and debris. Such was the velocity of the water, that it took only 1 hour and 40 minutes for the floodwater to reach the valley settlements of Singtam, (a distance of 92 km and a drop in gradient of 378 m); 36 minutes from Singtam to Kirney, near Melli, West Bengal (a distance of 25.4 km and a gradient of 120 m); and 30 minutes from Melli to Teesta Bazar, West Bengal (a distance of 4.2 km and a gradient of 10 m).
“While the GLOF in Sikkim might have been an ecological event, the disaster and destruction that ensued were definitely compounded by the cascade dams along the path of the Teesta. ”
It carried away everything on its path—people, homes, bridges, livestock, vehicles, and construction equipment. Severe damage to life, property and infrastructure was reported in four districts of Sikkim and downstream areas of north Bengal. Parts of National Highway 10, which had already been ravaged by monsoonal landslides and the incessant drilling and tunnelling for the upcoming railway line, were damaged, disrupting connectivity of people and goods.
As the day broke on October 4, and news and videos started to circulate, amidst the disbelief, fear, sadness, and helplessness, there was also a feeling of “we knew this would happen”. Living in the Sikkim-Darjeeling Himalaya, we have been helpless spectators to the relentless incursion of hydropower projects on the Teesta and its tributaries. We lamented over dams that transformed the free-flowing Teesta into a sluggish lake, the tunnels that bore deep into the hills, the scars of dry riverbeds, and the loss of everything attached with the free Teesta—culture, livelihood, memories, nature.
Hydropower projects are being relentlessly commissioned in a region that is prone to seismicity, landslides, and climate change-related disasters. The risks and hazards of infrastructural development in such an ecologically fragile zone are not hidden either from the government or from the hydropower developers. And yet they persist, waving the catchphrase of “sustainable development”.
While the GLOF in Sikkim might have been an ecological event, the disaster and destruction that ensued were definitely compounded by the cascade dams along the path of the Teesta. Combined with other anthropogenic activities (urbanisation, deforestation and infrastructure development), hydropower projects have worsened the pre-existing “hazardscape”, producing new geographies of uneven risks.
The GLOF potential of the South Lhonak Lake and the impact on downstream areas were known to the government. However, no effective early warning system or well-coordinated chain of command for such eventualities was in place. For instance, the Indo-Tibetan Border Police stationed in north Sikkim had alerted officials in Gangtok and Chungthang about the floods, and yet 23 soldiers were swept away from the army barracks at Bardang, located 1 hour and 30 mins downstream of the flood.
There are countless stories of victims not being alerted about the flood by legitimate sources; some recalled mistaking the evacuation alarm sounds for ambulance sirens; others thought it was just a mock drill. Local police and administration resorted to rudimentary alarm systems, using loud hailers and sirens to evacuate people. Thankfully, most people from the downstream areas were successfully evacuated in time.
Who is accountable?
A few days after the floods, I visited Singtam and Rangpo, two of the most severely affected towns. In both places, settlements near the riverbanks had completely gone under sand and silt deposits. I walked across what was now a flat plain of sand, littered with debris of personal belongings, household items, packaged goods, and half submerged cars and construction equipment—I was walking on top of what was people’s homes, neighbourhoods, and shops, all under 15 feet (5 metres) of sand now. Excavators worked tirelessly to dig out roads, houses, trucks, and human remains from under the sand. There is still no confirmation on the death toll, as no one has a record of the exact number of people living in the houses here.
Volunteers helped remove the still wet slush and mud from homes and shops, some distributed food and relief materials. Many flood victims returned with the hope of salvaging anything that they could from the sludge. People and government agencies came together to raise funds, collect clothes and other essential supplies for the victims, and engage in rehabilitation efforts. While these efforts on the ground continue, it is also imperative to ask, how did we get to this situation in the first place? Who is accountable and what does the future hold for Himalayan rivers and people?
Sikkim is a resource-poor State. There are no minerals that can be mined commercially, and the mountainous topography makes the establishment of large industries cost-inefficient. “Development”, which translates to better infrastructure, employment, modernity, and a higher living standard, rests on the tripartite strategy of tourism, industrial growth (particularly pharmaceutical manufacturing and hydropower projects), and the infrastructure that connects and enables these sectors. Sikkim aspires to pioneer a specific form of development, one that combines a public commitment to environmental stewardship (the category of Green State or Organic State) with resource extraction by private companies.
The State is rapidly becoming a lucrative backyard for Indian capital by offering extremely generous incentives for private investment. In the front yard, so to speak, the creation of a narrative about a modern, clean and simultaneously exotic and ecologically rich landscape is crucial to the way development is undertaken, financed and legitimised.
Here, hydropower projects need to be seen for what they enable—corporate greed, land-grabbing, corruption, privatisation of the commons, and collusion of the private and public sectors. The notion of hydropower as green energy has been blended seamlessly with the discourse of green and organic Sikkim, to validate the proliferation of huge dams across the fragile Himalayan environment.
Privatisation and deregulation
Despite its perennial rivers and strong potential for hydropower, Sikkim remained relatively isolated from the national energy market until the early 2000s. New programmes like the Mega Power Policy, 1995 (which arrived in Sikkim a decade later); Policy on Hydro Power Development, 1998; and the New Hydro Power Policy, 2008, were instrumental in accelerating hydropower exploration in the region. Perhaps one of the most important policies in this regard is the national Electricity Act, 2003, which allowed renewed privatisation and deregulation with an aim to attract investors to the renewable energy market. It enabled the entry of new private investors with very limited accountability and experience in the construction of hydropower dams on Himalayan rivers.
The Act was welcomed by the Sikkim government, and by 2007, 24 Memorandums of Understanding had been signed with hydropower developers, a majority them private companies. The implementation of these policies compelled a partial shift in the role of the State government—from the provider of social welfare to a champion of private investment and market penetration.
“Rivers and communities along the Teesta basin have been suffering on account of hydropower projects for decades now.”
- On October 3, 2023, a Glacial Lake Outburst Flood (GLOF) from South Lhonak Lake in North Sikkim breached, causing massive devastation. The 1,200 MW Teesta III dam downstream was destroyed, resulting in 40 lives lost, 76 missing, and extensive damage to infrastructure.
- Hydropower projects in the region, including the Teesta III dam, have been developed despite the known risks of seismicity, landslides, and climate-related disasters. Such projects have exacerbated the vulnerability of the region to natural disasters.
- Despite protests and controversies, the government has supported hydropower projects in Sikkim, leading to negative impacts on local communities and the environment. The recent disaster has prompted investigations, but long-term change remains uncertain.
This gave rise to controversies and confrontations. In 2007, the Affected Citizens of Teesta (ACT), an organisation of indigenous Sikkimese people, led a powerful and successful movement against the construction of hydropower dams in north Sikkim. The ACT was successful in presenting hydropower development as a threat to the culture, history, and sacred landscape of the indigenous Lepcha community of Sikkim. Prior to this, in 1997, the 30 MW Rathong Chu project in Sikkim had been cancelled after large-scale protests by Buddhist leaders and monks. In the aftermath of the 2007 agitation by ACT, a large number of projects were either stalled or cancelled by the State government. But in recent years, many hydroelectric projects contracted to private companies have started again, away from the public eye.
Overwhelming negative impact of dams
Rivers and communities along the Teesta basin have been suffering on account of hydropower projects for decades now. Reservoir dams divert the flow of rivers to a system of tunnels burrowed under hills, leaving vast stretches of the riverbed dry for long periods. Dams change the volume and flow of rivers, making it risky for local people to bathe, fish or perform cremation on the riverbanks. The pondage behind the barrage floods the land, causing families to abandon their homes, often without fair compensation. In many places, the network of concrete tunnels under the hills has diverted underground water away from springs and other outlets, exacerbating the water crisis in drought-prone areas.
And yet, the political conversation and blame-game continues to revolve around sub-standard dam construction rather than around a re-assessment of dams as a model of sustainable, economic development, especially when negative impacts outweigh any negligible (or non-existent) benefits to local communities. Recently, the Government of Sikkim formed a high-level committee to investigate the allotment process of the Teesta III project, with a view to assessing the credibility, technical know-how, and financial stability of the developers.
Chief Minister Prem Singh Tamang, said in a Facebook post that his Cabinet had directed the Sikkim Vigilance Police to conduct a “comprehensive inquiry to find out whether there is any criminal angle in the whole process of construction of the project and submit a report for registration of the case of transfer to CBI.” A political gesture that is perhaps too little, and definitely too late.
In every likelihood, once public anger abates and political interest shifts to other issues (like the general election next year), it will be business as usual. In the absence of an active and all-encompassing civil society movement focussing on environment and development in Sikkim and the eastern Himalaya, the government will rehabilitate victims while building more dams. The ACT has been protesting tirelessly against dams since 2007. Perhaps it is time for more of us to be engaged and invested, to do more than just lament over what happens to our hills, rivers, valleys and mountains, which are our home.
Mona Chettri is a researcher from Gangtok, Sikkim. She is the Research and Capacity Building lead at Reading Himalaya, a research and policy consultancy focussing on the eastern Himalaya. Her research focuses on the intersections between environment, gender, development, urbanisation and politics in the eastern Himalaya of India and Nepal. She is the author of Constructing Democracy: Ethnicity and Democracy in the Eastern Himalayan Borderland and series editor of the Eastern Himalaya series (Rachna Books and Publications).