A view shows a damaged barrage after a part of a glacier broke away causing glacial flood in Chormi village in Tapovan, in Uttarakhand, India, February 7, 2021. Photo: Reuters/Stringer
The flash flood on Sunday (February 7, 2021) morning in the Rishiganga river, of the Garhwal Himalaya of Uttarakhand, caused a huge devastation and presumably killed more than hundred people. The exact cause is yet to be ascertained, but the event is similar to the Kedarnath flash floods in 2013, when the Chorabari Glacier melted and flooded the Mandakini river. Clearly, this is an overbearing consequence of the continuous human plundering with the environment.
The Himalayas are battered by construction of dams and rampant urbanisation. A recent study suggests that with the current rate of deforestation, only about 10% of the land area of the Indian Himalaya will have dense forest cover by 2100. The latest offence is perhaps the Char Dham National Highway, which the Centre is building at an estimated cost of Rs 12,000 crore. With a 12-metrewide all-weather road stretching over 900 km, the project intends to connect the major Hindu pilgrimage sites of Badrinath, Kedarnath, Gangotri and Yamunotri in Uttarakhand. Considerable work has already been carried out by three implementing agencies namely, PWD, Border Roads Organisation and National Highways and Infrastructure Development Corporation Limited.
The construction has disrupted the geology and ecosystem of the Himalayas. The project proponents bypassed an environmental impact assessment – a mandatory requirement for such long roads. Under public pressure, the Supreme Court subsequently constituted an expert committee, with noted environmentalist Ravi Chopra as chairman plus a group of geoscientists, in August 2019.
This committee’s report stated that the road construction had dealt “irreversible damage” to the Himalaya in the region. A disregard of the geology and the unscientific manner of excavation had created at least a hundred new landslide zones. More than 50,000 trees had been cut, causing slope failures. The recurrent dumping of muck and other debris also took a heavy toll on nearby forests, river valleys and villages.
The work also left rivers and water bodies polluted and choked, and the habitats of musk deer and snow leopards in adjoining wildlife sanctuaries were imperiled.
The basic principles of geotechnical engineering suggest that a region where annual rainfall is more than 1,000 mm, and where earthquakes, flash floods and cloudbursts are common, excavating slopes at an angle of more than 35º can be hazardous. This is because steeper slopes are less stable.
Excavation for construction has also degraded the serene landscape. The stretch from Guptkashi to Kedarnath has considerable slope instability and experiences several avalanches every year. This area is also dangerously close to the earthquake-prone main central thrust fault of the Himalaya. So human interventions, like constructing wide roads, will amplify the natural hazards and also create difficulties for the pilgrims visiting these stretches.
Indeed, the whole episode is a classic case of anthropogenic destabilisation of a natural system that, ironically, is essential to sustain the area’s human population. The Himalaya are not simply a mountain chain. They are part of Earth’s “third pole” – home to the largest number of glaciers outside the polar cryosphere. According to the 2019 Intergovernmental Panel on Climate Change , the Himalaya are under considerable threat thanks to global warming, atmospheric aerosol pollution and land use change. In the best case scenario of a 1.5º C increase in average surface temperature by 2100, 50% of the Himalayan glaciers are likely to melt away.
The habitat ecology of endangered animals like snow leopards are likely to be lost in this process, due to shifting tree lines. The report also envisages a more than 20% increase in annual rainfall as well as more extreme monsoons. These factors could all contribute to catastrophic avalanches and glacial lake outbursts.
We must know how the destruction of ecosystems can trigger viral pandemics, like that of COVID-19, and bring humankind to its knees. We are in no position to presume that any other destructive enterprise in the region won’t have the same consequences.
Anindya Sarkar is a professor and former head at the Department of Geology and Geophysics, IIT Kharagpur. The views expressed here are the author’s own.