Uttarakhand glacier disaster: What caused the deadly flash floods in India?

A landslide, or a glacial collapse? Scientists are divided over what unleashed the deadly flash floods in northern India’s Uttarakhand state on Sunday that swept away everything in its path. But for activists in the region, the cause is crystal clear.

In 24 hours of rescue operations, the Indian authorities have recovered over a dozen dead bodies with more than two hundred people still missing. The flood washed away hundreds of houses and roads, raising fears of a repeat of a 2013 disaster which killed almost 6,000 people, according to government figures. 

The heavy flow of water also damaged several dams, including an under-construction hydroelectricity project. Dozens of workers building one of the new plants became trapped under two tunnels, with over 18 rescued as of Monday evening. Most of the people reported missing were construction or dam workers, and are now feared dead.

Initially, it was widely reported that the floods were triggered by a glacial lake bursting. However, some experts have also theorised that an initial landslide may have been the cause. Investigations into precisely what caused such a huge and sudden flood will take time, as a team of scientists studies evidence in the area with authorities forming committees to discuss the results.  

What we do know is that despite repeated disasters, little has changed in the functioning of a Himalayan state that is extremely vulnerable to natural calamities. This is partly due to its geography but, if activists are to be believed, also partly down to the many infrastructure and development projects in the area disturbing its natural ecosystem.

Activists have been warning of impending disasters for years now as the government continues to approve plants and construction in the fragile area. 

“The concerns that we had in 1988 are the same that we have today,” Vimal Bhai, a long-time activist with civil rights group Matu Jan Sangathan, tells The Independent. 

“This is not the first time a disaster of this scale happened. It has been happening repeatedly. A disaster took place in 2010 and 2013, and when we managed to overcome it, another disaster came knocking on our door,” he says, adding that there is no doubt in his mind “that the large dams over the river have increased the natural disasters”.

He says the recent constructions in the area have all been “violating every environmental norm”. 

“Local administration does not restrict the companies and they continue working in their own way, and the results are seen in the form of disasters like these,” says Bhai, who has been working to protect the fragile area and its residents for years. 

After the 2013 floods, a committee set up by the Supreme Court recommended that no more dams be constructed in the state. Despite that, the government has since approved five more dams in the area which suffered the floods on Sunday. 

“Why do you need to build these massive projects on a fragile land? Who needs this? Only contractors,” the activist says, alleging that the projects often get clearance from the government because they have powerful, well-connected companies involved. 

India also has major gaps when it comes to disaster management plans for its hydropower projects. According to a report by the country's Comptroller and Auditor General (CAG), only 349 out of the 5,334 large dams in India have a disaster management plan in place. 

Activists also allege the government is ignoring the climate crisis in the region, which is worsened by the high-intensity construction and detonations by companies in the area. 

Though it is not yet possible to determine the exact role that climate change could have played in the disaster, scientists have previously warned that the Himalayas and its surrounding glaciers are extremely vulnerable to warming.

A study published in 2019 found that the rate of glacier retreat in the Himalayas has doubled since the late-20th century. From 2000 to 2016, the Himalayas lost an average of eight billion tonnes of ice per year, according to the results. A second report found that the Himalayas and Hindu Kush region could lose at least a third of its ice by 2100, even if the world’s climate goals are met. 

Stephan Harrison, professor of climate and environmental change at the University of Exeter, says: “The recent tragic disaster in Uttarakhand has been reported as being triggered by a glacier collapse.  However, the evidence so far available suggests that it was a large landslide that created the devastating flood. 

“Several people on social media have also argued that climate change is responsible, but attribution to a climate driver is likely to be extremely difficult.  What such events do show is that development of infrastructure such as hydroelectric power in high glaciated valleys requires a good understanding of the likely climate and geological risks in such rapidly evolving systems.”