Before flood catastrophe, Nepal asked China for early warnings as risks mounted

Highlights:

• Nepal sought data access from China when scientists met in May
• China says it has shared information in a 'timely manner'
• Climate change raises risk of flood, landslide

Three months before a wall of water, mud and rock killed hundreds when it hurtled down a Himalayan valley bordering Nepal and China, experts and officials from both countries met in Kathmandu to discuss the risk of such disasters.

At the 27 May meeting in Nepal's capital, 10 officials from Nepal and about a dozen from China, including the Tibet region where the disaster struck, discussed strengthening cooperation to monitor and respond to floods, weather and glacier-related hazards, according to ​an agenda prepared by the Nepali side and seen by Reuters.

The participants called for joint risk-reduction measures, including inventories of glacial lakes and hazard mapping.

But two Nepali officials told Reuters they did not receive as much information as they wanted from China on glacier risks and ‌water levels after the meeting and they feared insufficient data sharing could hamper their ability to anticipate and prepare for major disasters.

"What we actually wanted from them, and still want, is if there are early movements of glaciers and early movements around that area, we would want to know a bit early," said Sauhardra Joshi, a hydrologist at Nepal's Flood Forecasting Division, who was in the May meeting.

China says its data sharing has been 'timely'

No officials or experts have blamed either side for the natural disaster, which will cost an estimated tenth of Nepal's annual economic output to recover from. Nepali officials say the priority is to deepen cooperation with China.

China's foreign ministry did not respond to a request for comment on the May meeting or on Nepal's request for additional information sharing.

At the meeting, the Chinese said ​they did not have the mandate to sign an agreement to meet Nepal's requests, asking for further discussions, said Binod Parajuli, another Nepal government hydrologist.

Details of the meeting and Nepal's demands for broader cooperation in monitoring the glaciers that threaten communities on both sides of the border have not previously been reported.

China's embassy in Nepal said in a statement on X on Saturday that Beijing and Kathmandu had kept in close contact on the issue and had made "substantial progress" at the meeting in May on promoting cross-border disaster information sharing.

Nepal raised similar concerns last ⁠year, officials said, though experts and officials cautioned that what they describe as slow progress was not a significant factor in the latest disaster, in which a glacier collapse unleashed a catastrophic mudslide that has killed nearly 800 people in both countries and left more than 3,000 missing, by the latest count.

Rejecting criticism from some Nepali social media ​users that China had failed to provide adequate warning, the Chinese embassy said Chinese and international experts faced significant challenges monitoring hazards in the remote Himalayan region.

Chinese teams had shared important information with Nepal "in a timely manner", it said.

At last year's meeting, Nepal raised concerns about a flood in the same area, triggered by the sudden release of ​water from a glacial lake in Tibet that killed at least nine in Nepal and left more than a dozen missing.

"When the Chinese side sees a heavy precipitation forecast in the Tibet area, then they provide us that forecast and those observations," Parajuli said. But "not for avalanche and water level, landslides, extreme events."

China began sharing forecasts of heavy rain in Tibet over China's WeChat messaging app and email a month ago, Parajuli said.

Timeline to calamity

Twelve days before the disaster, China's World Meteorological Centre told Nepali officials in an email, seen by Reuters, that a monsoon depression was forecast for the area from 14 to 19 August.

"Enhanced rainfall is likely across much of Nepal, and we wish to draw your attention to the potential for secondary and cascading hazards, including but not limited ​to landslides and flash floods," China warned.

The Chinese embassy said China has been sharing information including monitoring data on a lake formed by debris from last week's calamity.

The discussions over data-sharing underline the complexity of monitoring, forecasting and providing early warning in a region where regional geopolitical rivals — including China and India — control remote mountainous areas holding ​vast quantities of ice and snow that loom over densely populated South Asian plains.

Wednesday's catastrophe was sparked by the collapse of the glacier in a relatively unmonitored area, and a lack of bilateral cooperation was not a significant factor in Nepal's response, according to environmental anthropologist Austin Lord, senior fellow at the Washington-based Stimson Center think tank.

"That's not to forgive the fact ‌that there isn't really ⁠a well-articulated system. And there is very limited exchange between Nepal and China," said Lord, who is part of a team supporting Nepal's government on disaster and climate risk management.

"Chinese scientists have a much greater capacity, have much greater resources for monitoring than those on the Nepal side overall."

The time that the torrent took to reach Nepal shows the value of early-warning systems, Parajuli said.

Around 8:32am Nepal time on Wednesday, the deluge blasted through a border crossing in Tibet as people attempted to flee, according to surveillance footage that has become a defining image of the disaster.

Twenty-six minutes later, Parajuli got a call from the chief of Nepal's National Disaster Risk Reduction and Management Authority, alerting him to a flood on the Trishuli river. Parajuli's team found that a border monitoring station had not transmitted any data since 8:40.

"We also then tried to contact downstream stations, but downstream stations also couldn't post the data," leaving the team to suspect those devices had been washed away, he said.

After contacting local Nepali authorities to confirm the flooding, Parajuli ​said, his team sent a public alert to mobile phone users at 9:13.

At least ​four monitoring stations were destroyed by the flood that rampaged 168 km (104 miles) ⁠downstream from the Nepal-China border, carrying some 57.4 million cubic metres (2 billion cubic feet) of water, more than half again as much as normal, according to a Nepali government assessment.

'Huge gush of mud coming straight at us'

Surging floodwaters, which dislodged giant boulders and pulled large buildings into the overflow, damaged 19 bridges and some 40 km (25 miles) of highway, and knocked out more than 10% of Nepal's power-generation capacity, according to the Stimson Center.

"It wasn't water. It was a huge gush of mud coming straight at us," ​said Keshav Prasad Baral of Tupche village, about 25 km (15 miles) downstream of the border. "I tried to grab my wife's hand, but she was swept away by the mud."

When part of the glacier broke away, crashing to the valley floor ​hundreds of metres below, it unleashed high-speed flash ⁠floods, according to preliminary assessments by Nepali authorities.

The Hindu Kush Himalayas, home to hundreds of millions of people from Afghanistan to Myanmar, contain the world's largest volume of ice outside the poles, with more than 63,700 glaciers covering nearly 56,000 square km (22,000 square miles), almost the size of Croatia, and storing up to 5,700 cubic km (1,400 cubic miles) of ice.

By comparison, the glacier chunk that caused the latest disaster carried an estimated 5 million cubic metres of ice and rock, according to Basanta Raj Adhikari, director of the Centre for Disaster Studies in Nepal's Tribhuvan University.

Driven by climate change, glacier melt is accelerating as snow cover declines and snowfall becomes more erratic, according to a 2023 study by the International Centre for Integrated Mountain ⁠Development.

These changes will increase ​the likelihood of floods and landslides, as mountain communities also deal with such hazards as sedimentation and erosion, the centre projects.

Several of Nepal's major river systems originate in Tibet, then flow through one of ​the world's most seismically active and flood-prone regions.

Nepal's authorities will seek to work with China to conduct research and build systems to monitor avalanches and the release of water from glacial lakes — major risks for mountain communities — Parajuli said.

He said his department will propose a data-sharing agreement with China, along the lines of an arrangement that Nepal has with neighbouring India, for more frequent information on precipitation and river levels, ​not just high-precipitation forecasts.

Nepal will seek data every 10 minutes so that "we can warn our people, save our people," he said. "Our main target is we shouldn't miss any future disaster."