Sikkim flash floods | The river runneth over

A massive flood resulting from a glacier-lake outburst in Sikkim wreaked havoc in the early hours of October 4. It claimed at least 94 lives and destroyed the Chungthang dam, which is critical to the Teesta-III hydropower project. Rahul Karmakar reports on the tragedy and the conversations on dam building in a fragile region

October 14, 2023 04:11 am | Updated October 30, 2023 09:14 pm IST

Vehicles that got washed away in the floods lie in the sand along the Teesta river in Rongpo, Sikkim.

Vehicles that got washed away in the floods lie in the sand along the Teesta river in Rongpo, Sikkim. | Photo Credit: Ritu Raj Konwar

There is a popular folk tale in Sikkim, told and retold in regions where the Lepchas live. The Lepchas are one of the three main ethnic groups of the State, the others being the Bhutia and Nepalese. The story goes that the male river Rangeet, angry after having lost a race downhill to the female river Rungnyu, turned from the spot of their proposed meeting back towards the Himalayas with an intensity that wreaked havoc in the region. In 2021, a song gave a modern twist to this folk tale. The song of resistance sung by Ongyal Lepcha goes, “I can drown everything that stands. Do tell them, so many rocks and hills I have cut through, how can these little hurdles hold me back?” The song apparently refers to the rage of the river, at the slew of hydropower projects in Sikkim.

On October 4, the song proved to be prophetic not for the Rangeet but for the Rungnyu, popularly known as the Teesta. The South Lhonak glacial lake, formed from the gradual melting of a Himalayan glacier and located about 17,000 feet above sea level in north-western Sikkim, suddenly breached its embankments and “burst”, inundating the Teesta river basin. This caused flash floods, which swept away 14 bridges and the dam of a 1,200-megawatt hydropower project, damaged 1,825 houses, claimed at least 94 human lives, and forced 2,563 displaced people into 21 relief camps, according to government data. Seventy-eight people are reported missing.

The damage in Rangpo and Singtam

Bishnumaya Shanti, 70, a homemaker, is familiar with the folk tale. She says she had experienced the Teesta’s destructive mood in October 1968, the last time the river had inflicted large-scale damage. “But that was nothing compared to what the river has done to us today,” says Shanti whose house, built with the life savings of her family, was swept away. She is now at the Majigaon community hall-turned-relief camp near the police station in Rangpo town. This is the point of access to Sikkim via National Highway 10 from West Bengal. Shanti is heartbroken about losing all her belongings, but she is more relieved that all the members of her family managed to escape the river’s fury in the nick of time.

Flood victims take shelter in a relief camp in Rongpo.

Flood victims take shelter in a relief camp in Rongpo. | Photo Credit: Ritu Raj Konwar

Rangpo, in Pakyong district, has a population of 10,450 people. This is where the Rangpo river meets the Teesta. It was most badly hit by the floods along with Singtam, a major market 11 km upstream of the Teesta on the road to Gangtok, the State’s capital. An Army unit at Bardang in between these regions was buried under debris. At least 23 personnel were swept away.

At Singtam, Prakash Pradhan, a trader, recalls watching in disbelief as the iconic Sherwani bridge across the Teesta facing his four-storey building swayed against the surging water and debris for about two minutes before giving way. The bridge connects Singtam in Gangtok district with Namchi, the headquarters of South Sikkim district. “As the water level kept rising and our first floor was half submerged, we rushed to the roof, hopped onto the top of the next building and the next until we were at a safe distance from the river,” he says. It was about 3:30 a.m. and raining hard.

Also read | Damages due to Sikkim flash floods worth thousands of crores of rupees, says CM Tamang

Pradhan and the residents of some 2,000 dwelling units in Singtam’s market area returned the next morning to find their houses buried in about 15 feet of sand. The local administration advised two of his neighbours not to return to their houses. Both their buildings were cracked and hanging precariously over the river. A footpath behind them had already been swallowed up by the river.

Rongpo town was devastated by the flash floods , east Sikkim on 11 October 2023. The cloudburst occurred over Lhonak Lake in North Sikkim leading to the flooding of the river which flows through Sikkim and West Bengal. Photo: RITU RAJ KONWAR / The Hindu

Rongpo town was devastated by the flash floods , east Sikkim on 11 October 2023. The cloudburst occurred over Lhonak Lake in North Sikkim leading to the flooding of the river which flows through Sikkim and West Bengal. Photo: RITU RAJ KONWAR / The Hindu | Photo Credit: Ritu Raj Konwar

“At least 18 people from our area are either dead or missing. They probably had no time to react to the river’s fury,” says Vishal Rai, a college student from the West Bengal part of Rangpo.

While Sikkim — aided by the Army, Border Roads Organisation, and other agencies — has been prompt in responding to the disaster in four of its districts, West Bengal is yet to assess the damage across the Kalimpong, Darjeeling, Jalpaiguri, and Cooch Behar districts through which the Teesta flows before meeting the Brahmaputra in Bangladesh. Access to Sikkim has been disrupted primarily because a 30-metre stretch of NH10 — that falls within the Gorkhaland Territorial Administration (GTA) in West Bengal — has been damaged.

“Many villages on the banks of the Teesta have been washed away and there are reports of several people dead and injured. We are holding an administrative meeting soon to assess the damage,” says Anit Thapa, GTA’s chief executive. The GTA, he adds, received ₹25 crore as assistance from the Mamata Banerjee government but nothing from the Centre, unlike Sikkim which received more than ₹44 crore.

Community service

The push for industrialisation led to Sikkim becoming a pharmaceutical hub more than a decade ago. The State has production units of 14 top Indian and international pharmaceutical companies, almost all of them along the Teesta, between Rangpo and Singtam.

The pharmaceutical boom led to an increase in real estate prices. Multi-storeyed buildings started coming up along the banks of the Teesta and its tributaries soon after the 2011 Sikkim earthquake that officially claimed 60 lives. A majority of the tenants are employees of these pharmaceutical companies.

Sanjib Tamang built his three-storey house at Rangpo in 2012 at an elevation considered safe from inundation during high floods. “This flash flood was much higher than what we encountered in the past,” he says. Tamang salvaged only about 10% of the goods in his silt-filled grocery shop and shifted his two tenants — both pharmaceutical employees — to his restaurant in the market on higher ground.

O.P. Niroula, who leased out his house to Sarthak Patnaik and Rajesh Sahu, both from Odisha, shifted them to his second house in the almost untouched Majitar town upstream of the Teesta. Unfortunately, they lost all their belongings.

A portion of the NH-10 was washed away by the flash floods near Gangtok.

A portion of the NH-10 was washed away by the flash floods near Gangtok. | Photo Credit: Ritu Raj Konwar

Rangpo resident H.N. Sapkota, who rescued about 150 people from drowning on that fateful night, says everything happened too fast for him to process. “Had I known nature would batter us, I would never have built a house here,” he says.

Teesta washed away the plot that Maita Hangma Subba, a homemaker, bought to build a permanent house. She had constructed a temporary structure and rented it out for a vehicle workshop, which was swept away along with a few vehicles. “I will probably think 10 times before deciding to build a house there,” she says pointing to the confluence of the Teesta and the Rangpo rivers.

Despite their losses, she and Sapkota have been central to preparing community meals for the rescue and relief workers – from the National Disaster Response Force, Sashastra Seema Bal, district authorities, members of NGOs, and villagers from places 50-60 km away.

“We are short of manpower but voluntary service from the people is seeing us through,” says Pakyong’s Deputy Commissioner, Tashi Chophel. He has been coordinating the evacuation of some 3,000 tourists stranded in northern Sikkim by Indian Air Force choppers to the Pakyong Airport. The exercise has been weather-dictated; 371 tourists were evacuated on October 9 and 10 but the choppers could not fly on October 11.

Buddha Bangar, a self-employed man, came with 50 people armed with spades and shovels from Namchi, about 55 km away, to clear the debris as fast as possible. Likewise, Dilu Tamang, who runs a dance academy in Gangtok, also about 45 km from Rangpo, came with about 80 members of her academy to collect relief materials and lend a hand in clearing the debris.

“Helping each other out is a community trait but the government is not depending on the people alone. An inter-ministerial central team is assessing the damage for the government to work on a comprehensive rehabilitation programme,” says Assembly Speaker Arun Kumar Upreti.

Blame game

The disaster in Sikkim and West Bengal downstream has been attributed to the glacial lake outburst flood (GLOF). The floodwaters from the South Lhonak glacial lake reached the 1,200-MW Teesta-III hydel project at Chungthang via the Lachen River. The 60-metre-high rock-filled concrete dam, Sikkim’s highest, is where the Lachen meets the Lachung to flow down as the Teesta. An investigation is being conducted to ascertain if the dam’s spillways or openings to allow excess water to flow out were opened before the floodwaters from the GLOF reached Chungthang, which is about 55 km downstream of the lake.

Teesta-III had a gross storage capacity of 5.08 million cubic meters and a live storage capacity of 3.3 million cubic meters. The combined discharge of storage water and GLOF from Teesta-III hit the NHPC’s 510 MW Teesta-V and the under-construction 500 MW Teesta-VI downstream in about an hour, causing considerable damage.

Sunil Saraogi, the executive chairman of Sikkim Urja Limited, which operates the hydropower project, says the project operators received information from the Indo-Tibetan Border Police about the GLOF at 11:58 p.m. on October 3.

“Our team of 12 or 13 people headed to the dam at Chungthang to open the gates, but the flash floods struck before they could act, forcing them to flee for their lives. The dam got washed away in 10 minutes after midnight. The bridge connecting the powerhouse was also washed away,” he says. Eleven employees of the project have been missing since the flash floods.

The Sikkim government has a 60.08% stake in the Chungthang project. Sikkim Chief Minister Prem Singh Tamang attributed the disaster to the “substandard construction” of the Teesta-III dam at Chungthang and said the Sikkim Democratic Front (SDF) government headed by Pawan K. Chamling was to blame for it. The BJP legislator representing the Gangtok seat, Y.T. Lepcha, went to the extent of filing a police complaint against Chamling. However, the BJP, an ally of Tamang’s Sikkim Krantikari Morcha which Tamang belongs to, softened its stand later. “This is not the time to blame each other but to work together for seeking more funds from the Centre to deal with natural disasters better,” stated State BJP spokesperson Dolaram Giri.

The SDF said the Chief Minister was trying to score brownie points with the Assembly elections due in the first part of 2024. “There should be a forensic probe by central agencies into the dam break. Before making flippant statements, the Chief Minister should realise that Chungthang was given environmental clearance by the Environment Ministry, and technical clearances by the Central Water Commission and the Central Electricity Authority. It has become a habit for him to blame the SDF for everything,” SDF leader M.K. Subba says.

Warning failure

The Lepchas who revere the Teesta believe that Chungthang should not have been built in the first place. “The State government pushed the project despite two years of hunger strikes against it from June 2007 to September 2009. Our worst fear about Chungthang became a reality although, thankfully, the disaster struck at night. Had it been during the daytime, the damage would have been much higher,” Gyatso Lepcha, the general secretary of Affected Citizens of Teesta (ACT), says.

High rise buildings on the bank of the Teesta river in Singtam area

High rise buildings on the bank of the Teesta river in Singtam area | Photo Credit: Ritu Raj Konwar

The ACT has renewed its demand for scrapping the Chungthang project and decommissioning the NHPC’s 510-MW Teesta-V located at Dikchu, downstream. Locals say the dam has become a threat to the people of Zang village.

Sikkim’s Forest and Environment Minister Karma Loday Bhutia has taken a stand against reconstructing the dam. “Our soil is very young, and North Sikkim is a landslide-prone area. So, I feel the construction of a dam is not advisable,” he says. But Sikkim Urja Limited insists that the dam and bridge have to be rebuilt for the State’s energy security, entailing a huge expenditure.

Khamsung Lepcha, a resident of Chungthang, claims the dam could have been damaged by Army explosives swept down from a unit at Chhaten, about 3 km upstream of Chungthang. This could have weakened the structure for the surging waters to burst through. “We saw fireworks in the river,” he says. There have been reports of Army explosives being recovered from the downstream of Teesta up to the Bangladesh border.

Sikkim’s Chief Secretary V.B. Pathak says there was no official confirmation about explosives having impacted the dam, but admits that the possibility needs to be examined. He also says that an Advanced Warning System was installed in September at the South Lhonak Lake and Sakochu Lake – both glacial lakes – jointly by the National Disaster Management Authority (NDMA), the Sikkim State Disaster Management Authority, and the Swiss Development Corporation. The system was to give reports to be monitored by the Swiss agency in consultation with the NDMA. “Most probably, the system was not working when this incident took place,” he says.

The police did sound the alarm in habitations along the Teesta but most residents took it to be a routine exercise. “The authorities should consider a different alarm system during an imminent major disaster,” says Karma Bhutia, a student helping out at Singtam.

Mayalmit Lepcha, president of the Sikkim Indigenous Lepcha Tribal Association, says Sikkim is “Mayal Lyang” or a land blessed by the gods. “How can it remain that way if we do not let our rivers, specifically the sacred Teesta, flow freely,” he says.

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