The increased demand for electricity has led to the construction of a large number of hydro power projects (HPPs) upstream near glacial lakes in the Himalayan region. But the melting glaciers pose a increased risk to HPPs. 2013 Uttarakhand tragedy has shown how torrential rains raised the water level of the Chorabari Lake in Uttarakhand, breaching the water levels in dams, leading to damaging of downstream HPPs.
• Thus it is important to factor in the large number of glacial lakes, the volume of water, flooding and distance between a dam and a glacial lake while constructing HPPs in the Himalayan region.
Causes of floods in Himalayan region:
Natural causes:
• Intense rainfall:Its topography is prone to cloud burst in the catchment’s region of the river that results in heavy rain and flash floods.
• Himalaya’s: Himalaya’s act as barrier to monsoon prolonging its stay and intensity.
• Melting of snow in Himalayan natural channel causes clogging & shifting the courses resulting in flooding.
• Topography: Its topography is prone to tectonic movement leading to slope failure and landslides leading to obstruction of flow and change in the river course.
Man made/anthropogenic:
• Unplanned infrastructure: Unsafe and unplanned infrastructure development along local rivers. Eg: development of a large number of hydropower projects built in the fragile zone without proper checks and balances.
• Unsustainable agriculture practices: Practices as Jhuming in NE Himalayas has led to
• Climate change: Climate change and global warming
• Ecological destruction by unplanned development: Encroachment of riverbeds and failure to preserve wetlands that acts as sponge leads to increased disasters due to flooding.
Thus as the region is prone to flash floods and increased melting of glaciers has to be factored in and incorporate extra design and safety features in the construction of hydro power projects in the Himalayan region.
