Energy SecurityHimalayan Hydropower “Clean but Risky”: Scientists

By Ranjit Devraj

Published 28 September 2021

The Himalayas, with steep topography and abundant water resources, offer sustainable, low-carbon hydropower for energy-hungry South Asia. But there is a catch — the mountain range falls in one of the world’s most seismically active regions.

With its steep topography and abundant water resources the Himalayas offer sustainable, low-carbon hydropower for energy-hungry South Asia. But there is a catch — the mountain range falls in one of the world’s most seismically active regions.

A group of 60 top Indian scientists and environmentalists wrote an open letter to Prime Minister Narendra Modi earlier this month seeking his intervention in stopping “any more hydroelectric projects in the Himalayas and on the Ganga whether under construction, new or proposed”.

The letter cites the Intergovernmental Panel on Climate Change’s sixth assessment report which says that the Himalayas have been affected by warming. The report warns that “rising temperature and precipitation can increase the occurrence of glacial lake outburst floods and landslides over moraine-dammed lakes” in high mountain Asia. Moraine consists of rocks and soil left behind by moving glaciers.

Hydropower, the world’s largest source of renewable electric power with1,308 gigawatts of installed capacity in 2019, is expected to play a critical role in decarbonising power systems, according to the International Energy Agency (IEA), an inter-governmental body.

Stretching 2,400 kilometres in an arc that includes the world’s highest peaks, the Everest in Nepal and K2 in Pakistan, the Himalayas rank high among global hot spots for developing hydropower, though only 20 per cent of the estimated 500 gigawatt potential has been tapped so far.

But that situation is rapidly changing with hydropower projects mushrooming along the Himalayan arc — which covers territory in Bhutan, China, India, Nepal and Pakistan — despite proven risks from quakes, landslides and glacial lake outburst floods.

The immediate trigger for the appeal to Modi was a decision by India’s Ministry of Environment, Forest and Climate Change to allow the restarting of seven controversial hydropower projects in the Himalayan state of Uttarakhand.

Three of these projects — Tapovan-Vishnugad (520 megawatts), Phata Byung (76 megawatts) and Singoli Bhatwari (99 megawatts) — have already been severely damaged by floods and landslides in 2013 and in February 2021. Several other hydropower projects in the Himalayas have also suffered similar damage.

In February, a glacial avalanche set off flash floods in the Rishi Ganga and Dhauli Ganga valleys in Chamoli district, leaving 250 people dead and extensively damaging land and infrastructure, including the Tapovan-Vishnugad project.