Nepal floods expose risks to hydropower in a warming Himalayas

DHADING, Nepal (AP) — Workers shoveled thick mud from a flood-ravaged power station in central Nepal this week, trying to restore electricity to more than 20,000 people.

The floods that swept through Nepal and China, killing hundreds and leaving thousands missing, have also overrun hydropower facilities, knocking out about 10% of Nepal’s power capacity.

Once the immediate aftermath of the disaster is dealt with, the question will be how to restore power plants, roads, bridges, schools and health facilities without exposing them to the same vulnerabilities, disaster experts said.

“Authorities have to take a hard look in the mirror now and ask how they will be rebuilding in these places. They will also have to take a close look at other projects in Nepal that have not been built yet, whether they’ll be approved after this event,” said Jakob Steiner, a geoscientist at the University of Graz in Austria, who is currently based in Dhaka, Bangladesh.

Rebuilding for resilience, not just replacement

Hydropower projects that were operating or under construction were fully or partly destroyed across Rasuwa, Nuwakot and Dhading, among the worst-hit districts.

Hundreds of workers in Nepal are unaccounted for from a dozen hydropower projects, according to the Independent Power Producers’ Association, Nepal. Many had taken shelter in the tunnels but are stuck, waiting to be rescued, according to officials.

“The tunnels are built to access hydropower infrastructure and to divert water,” Steiner said, describing the tunnels as big enough for trucks to pass through.

Apart from the hydropower projects, tens of kilometers (miles) of roads, multiple bridges and essential buildings like schools and hospitals have been destroyed.

Ramraj Narasimhan, a senior director with the Coalition for Disaster Resilient Infrastructure, said rebuilding should focus on continuity of services rather than trying to make every structure indestructible.

“If it gets damaged, let it get damaged, but can we build in redundancy in the system?” he said.

That can mean choosing a better location for construction, alternate routes, backup power, improved early warning and financial tools such as insurance to speed recovery, Narasimhan said. Risk assessments should examine where a river bends, where slopes are unstable and where a single failure could cut off several communities.

Narasimhan’s organization estimates that $124 billion worth of Nepal’s infrastructure is exposed to climate-driven disasters, creating the potential for hundreds of millions of dollars in losses each year. A report by the coalition earlier this year found that Nepal’s average annual losses are nearly $760 million from various disasters, while the country’s national disaster funds is only a fraction of this amount.

Climate risks grow for Himalayan hydropower

Climate scientists said the Himalayan region — which is warming faster than many other parts of the world — is particularly at risk from increasing global warming as a result of human-caused climate change.

Climate experts said the flooding adds to evidence that infrastructure planning in the Himalayas should account for disasters that are increasing as the climate warms. Glaciers across the Hindu Kush Himalaya are losing ice at an accelerating rate, while permafrost degradation, unstable slopes, glacial lakes and increasingly erratic rainfall are raising the risks of floods, landslides and debris flows, according to reports by Kathmandu-based climate research group International Center for Integrated Mountain Development.

The stakes are particularly high for Nepal because hydropower is both a foundation of its electricity grid and an important source of economic growth and export revenue. Much of the country’s potential is run-of-river hydropower, Narasimhan said, meaning facilities are closely tied to steep river corridors where land is limited and hazards can cascade quickly.

Steiner said smaller floods can sometimes be managed with diversions that keep debris and high flows away from expensive infrastructure and tunnels. But for events as large as the latest flood, he said, physical defenses may be overwhelmed. In those cases, early warning becomes the critical protection for people.

He said the flood was detected at the China-Nepal border after moving rapidly from its source, leaving little warning time upstream. But there was still time as the flood traveled downstream toward hydropower sites, raising questions about whether warnings could have reached workers sooner.

The disaster is also likely to intensify scrutiny of where future projects are approved. Himanshu Thakkar, coordinator of the South Asia Network on Dams, Rivers and People, said environmental, social and disaster-risk assessments need to reflect the specific landscape and past hazards of each valley, backed by land-use rules and stronger accountability.

Hydropower projects can themselves become “force multipliers” when large structures, debris and altered river channels add to downstream damage, Thakkar said. He argued that Nepal should also consider more decentralized solar power as part of a broader energy mix.

Thakkar said the question now is not only how fast Nepal can rebuild, but what it chooses to put back in the path of the next flood.

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Sibi Arasu reported from Bengaluru and can be followed on X at @sibi123. Reach him at sarasu@ap.org.

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