BEIJING — Catastrophic flooding along the China-Nepal border has highlighted the growing risks of natural disasters in the Himalayas, even as China, India and Nepal continue to expand infrastructure across the region.

The latest disaster killed more than 600 people and left thousands missing, according to reports at the time. There is no indication that the flooding was directly caused by human development. However, the scale of the destruction has renewed questions about how governments are planning and constructing dams, roads, tunnels, bridges and other major projects in one of the world’s most geologically fragile regions.

The Himalayas sit along active fault lines and contain rivers fed by glaciers. The region is highly vulnerable to earthquakes, landslides, floods and other natural hazards. Climate change is also contributing to increasingly unpredictable weather and glacial conditions.

China has been at the center of the region’s infrastructure expansion. Beijing views Tibet and its Himalayan borderlands as important to both national security and energy development. The country is pursuing a massive hydropower program, including a megadam on the Yarlung Tsangpo River that is expected to become one of the world’s largest power-generation projects.

The project is designed to take advantage of a dramatic elevation drop in the river by constructing tunnels through mountainous terrain. China is also expanding high-voltage transmission networks to carry electricity generated by hydropower, solar and wind projects toward major population centers in the east.

India has been developing its own infrastructure in the Himalayas, including roads, tunnels, railways and hydropower facilities. Its state-backed energy companies are also advancing large-scale hydropower projects downstream from China’s planned developments.

Nepal has likewise expanded hydropower construction along Himalayan rivers, with investment and financing involving both China and India.

The infrastructure boom is driven partly by growing demand for electricity and efforts to expand renewable energy. At the same time, roads, bridges and other projects can improve transportation and facilitate the movement of personnel and equipment in remote border regions.

Experts warn, however, that the Himalayan environment presents unusual engineering challenges. Construction can require blasting through mountains, altering natural terrain and creating reservoirs in areas already exposed to landslides, debris flows and glacial lake outburst floods.

The recent flooding demonstrated the vulnerability of existing infrastructure. In Nepal, more than 430 megawatts of electricity-generating capacity were reportedly knocked offline after 12 hydropower facilities were damaged by floodwaters. Additional projects under construction, representing hundreds of megawatts of planned capacity, were also affected, according to Nepal’s Ministry of Energy, Water Resources and Irrigation.

Rescue operations have also been complicated by the possibility of secondary disasters. Flooding and landslides linked to debris-blocked rivers and newly formed barrier lakes have threatened rescue workers and communities downstream.

The disaster has also raised concerns about cooperation between countries sharing Himalayan rivers. Rumors that the flooding was caused by a dam failure in China circulated after the disaster, although the claim was not supported by evidence. China’s Embassy in Nepal rejected such accusations and emphasized the importance of cooperation.

Chinese President Xi Jinping also expressed China’s willingness to assist Nepal’s rescue efforts. Authorities on both sides have been communicating about a potentially dangerous barrier lake, while researchers have also been monitoring developments.

Water-data sharing has previously been a sensitive issue between China and India because many major Himalayan rivers cross national borders. During recent talks, Chinese and Indian officials agreed to maintain communication on hydrological information and planned further discussions on transboundary rivers.

Scientists and regional experts say that better cooperation could become increasingly important as climate change alters the region’s risk profile. Infrastructure planners may need to consider not only the immediate geological conditions but also how extreme weather and glacial systems could change over the lifetime of major projects.

The central challenge is that the Himalayas are changing at the same time that governments are building on an unprecedented scale. Experts say countries will need stronger early-warning systems, better data sharing and greater coordination to monitor hazards that can cross national borders.

As climate risks become harder to predict, the question facing Himalayan nations is not simply how much infrastructure can be built, but how infrastructure can be designed to withstand an increasingly uncertain environment.

Source: CNN — The Himalayas are unpredictable. But countries are building there like never before