Nepal flash floods wash away dreams of clean, easy hydropower, Pg II

Key Highlights:

• Flash floods in Nepal on August 26 devastated several areas, causing over a thousand deaths and damaging at least 13 operational hydroelectric projects and one solar plant.
• An additional 15 hydropower projects under construction, with a planned capacity of 470 MW, were also damaged.
• The incident follows similar disasters like the February 7, 2021 Chamoli floods, the October 4, 2023 South Lhonak Lake disaster, and the August 16, 2024 Thame floods, highlighting climate change risks in the Hindu Kush Himalaya region.
• Nepal, which relies on hydropower for over 90% of its electricity, faces significant disruption to its energy supply and projected electricity export revenues of $200 million for FY2025-26.
• The International Centre for Integrated Mountain Development (ICIMOD) reported an 80% increase in suspended sediment load from the Hindu Kush Himalaya headwaters over the last six decades.

Detailed Insights:

• The August 26 floods severely impacted hydropower infrastructure along the Bhotekoshi and Trishuli river corridors.
• Increased sediment load in Himalayan rivers, driven by heavier rainfall, glacier melt, and thawing permafrost, is a major threat to hydropower plants.
• Hard mineral sediments like quartz and feldspar cause significant wear on turbines and infrastructure, leading to frequent and costly maintenance.
• The vulnerability of hydropower workers, often poor and migrant, to such disasters raises concerns about climate justice.
• Nepal has an estimated 83,000 MW of technical hydroelectric potential but its current installed capacity is 3,435 MW by 2025.
• The country had 4,063 MW of hydropower under construction and 16,029 MW planned, which are now at risk.
• Nepal's Energy Ministry has indicated plans to purchase electricity from India to cover anticipated shortages.
• Experts advocate for a risk-informed approach to designing and operating energy systems and developing effective early warning systems across the Hindu Kush Himalaya.
• Regional cooperation is crucial for designing resilient infrastructure that accounts for the changing climate and environment.

Key Concepts Involved:

• Hindu Kush Himalaya (HKH): A vast mountain range system in Asia, critical for water resources and highly vulnerable to climate change impacts.
• Sediment Load: The amount of solid material, such as silt, sand, and gravel, carried by a river, which can damage infrastructure.
• Glacial Lake Outburst Flood (GLOF): A sudden release of water from a glacial lake, often caused by the failure of a natural dam.
• Climate Justice: A concept recognizing that climate change disproportionately affects vulnerable populations who have contributed least to the problem.