Massive floods triggered by a suspected glacial lake outburst in Tibet recently washed away Nepal–China Friendship Bridge, damaged hydropower plants and key infrastructure in Rasuwagadhi.

The Department of Hydrology and Meteorology (DHM) has said that the devastating flood in the Lhende River along the Nepal–China border were likely caused by a glacial lake outburst in Tibet, China. Based on satellite images taken before and after the incident, the department concluded that a reduction in the size of the glacial lake suggests it burst, leading to the flooding.

The flood washed away the Friendship Bridge connecting Nepal and China and severely damaged the under-construction dry port at Timure, built with Chinese assistance. More than ten hydropower projects suffered damage, leading to a halt in the generation of around 250 megawatts of electricity, while construction of several other projects has also been disrupted.

Experts warn that the increasing frequency of glacial lake outbursts due to climate change is putting Nepal’s infrastructure—particularly roads, bridges, and hydropower projects—at heightened risk. Hydrologist Madhukar Upadhyaya noted that extreme weather events and rapid glacial melting triggered by climate change have been causing significant damage to such structures.

"Most of our infrastructure—be it roads, bridges, or hydropower plants—is built along or over rivers, making them highly vulnerable to floods and landslides," he said.

In July 2023, the bursting of an artificial lake formed by landslide debris in the Thulung (Lahure) River in Bhojpur caused about Rs 600 million in damage to two hydropower projects—Fedi Thulung Khola (4.3 MW) and Upper Ikhuwa Khola (14.5 MW). A year earlier, in June 2023, floods in Taplejung, Panchthar, Sankhuwasabha, and Bhojpur damaged 30 hydropower projects with a combined capacity of 463 MW, causing losses of around Rs 8 billion. The devastating 2021 Melamchi flood was also linked to climate change, according to a study by the Asian Development Bank.

While environmental impact assessments typically study river behavior and erosion near project sites, Upadhyaya noted that insufficient study of upstream hazards like landslides and glacial movement has contributed to growing damage.

"Today, a single river stretch hosts multiple bridges and hydropower projects. When a flood hits, it affects all of them, making the damage far greater than in the past," he said. "Climate change has altered rainfall patterns. Intense bursts of rain and the formation and sudden bursting of glacial lakes are increasing the scale of destruction."

Nepal aims to generate 28,500 megawatts of electricity by 2035, primarily through hydropower. But climate-related disasters are putting this goal at risk.

Ganesh Karki, president of the Independent Power Producers’ Association Nepal (IPPAN), stressed the need for early warning systems to minimize such damage.

"Previously, floods caused by blocked rivers were the main problem. But now, damages are occurring even without rainfall, which means we must enhance our safety protocols," Karki said. Discussions have begun among hydropower developers to install early warning systems—such as sirens that can go off 5 to 10 days in advance of potential disasters.

Karki suggested that if such systems were installed in each river corridor, physical and human losses could be significantly reduced.

Experts warn that climate change is weakening the stability of mountain slopes, rocks, and soils in the Himalayas, increasing the risk of large-scale disasters. The World Bank’s Country Climate and Development Report 2022 stated that irregular rainfall, glacier melting, landslides, and glacial lake outbursts pose serious risks to Nepal’s hydropower infrastructure.

However, the report also noted that glacial meltwater could provide increased water flow, which could be harnessed for power generation if managed properly.

Devendra Raman Khanal, CEO of Rastriya Banijya Bank, said growing damages from floods and landslides are increasing investment risks in hydropower. “These risks are not unique to Nepal. Climate change has become a global threat,” he said.

Still, Khanal emphasized that banks are not shying away from energy sector investments. As of mid-May 2025, banks and financial institutions have invested 9 percent of their total loans—about Rs 478.75 billion—in the energy sector, according to the Nepal Rastra Bank. Despite the risks, investment in power projects continues to grow steadily.

“If we stop investing in infrastructure projects due to natural disaster risks, nothing will be built,” Khanal said. “Just like the tourism industry rebounded after the COVID-19 crisis, we are seeing momentum in hydropower expansion despite the challenges.”