Kedarnath avalanches: An expert committee was formed by the Uttarakhand government to probe a series of Kedarnath avalanches in the past two months. They advised a complete ban on construction of buildings and temporary shelters on the “highly unstable and active debris slope above (the) Kedarnath temple”.
A report was submitted to the government which told the government in Uttarakhand to instead build concrete wedges and mounds on the higher slopes above the temple. This would reduce the momentum of avalanches originating about 5-6 km above the shrine.
Three Kedarnath avalanches were reported from the hills surrounding the shrine in Uttarakhand’s Rudraprayag district, between 22 September and 2 October. All were reportedly at a distance of 3-4 km from the temple site.
Last year, on 23 April, a temporary shelter housing labourers working for the Border Road Organisation (BRO) killing 16 people. A few months later, on 2 October, seven mountaineers lost their lives in an avalanche near mount Trishul.
In 2013, flash floods and landslides in the Kedarnath area wreaked havoc, killing many.
The expert committee report also mentions other avalanches from further back. One was in October 1998, which killed 27 pilgrims. Another happened on 23 June, 2008, when 20 people, including eight pilgrims, were severely injured. More than 100 lives have been lost in avalanches in the higher hills of the Chardham region in the past 10 years, according to the report.
On 1 October, following two of the past months’ three avalanches, the Uttarakhand government constituted an expert committee to undertake geological, glaciological, and geomorphic investigations around Kedarnath.
The five-member panel included the executive director of Uttarakhand State Disaster Management Authority (USDMA) Piyoosh Rautela, Wadia Institute of Himalayan Geology scientists Manish Mehta and Vinit Kumar, and Indian Institute of Remote Sensing’s C.M. Bhatt and Pratima Pandey — were tasked with ascertaining the causes of recurring avalanches in the area, assess risk factors and suggest remedial measures.
In its report, the panel recommended a “complete ban” on construction of any form on the highly unstable and active debris slope. Including scree fans (fan-shaped rock fragments). Construction activities at such heights may “lead to changes in direction and slopes of the unconsolidated materials” between the avalanche sites and the shrine.
The report also recommended slope modification and structural changes on the slopes.
“Benching of the slope at different elevations along the steep gradients of snow drift or channels to the north of Kedarnath temple would reduce overall slope angle and retard the velocity of downward movement of snow and debris mass” added the report.
It was also suggested that concrete wedges be constructed along the mid-slope of avalanche chutes to prevent and divert the forces, for “total protection from avalanche hazard”. The design, size and number of these structures would be decided after detailed field studies.
Kedarnath avalanches – Origin in glaciers
According to the report, the three recent Kedarnath avalanches originated 6 kilometers above the temple. From the peaks of the Companion Glacier adjacent to the Chorabari Glacier.
The town of Kedarnath is located on the outwash plains of Chorabari and Companion glaciers. The channels of the Mandakini river originate from Chorabari and Saraswati. It flows down from Companion glacier, encircling the plane terminating towards the south of the temple — the meeting point of the two rivers.
According to the report, “These streams (Mandakini and Saraswati) are observed to actively erode their banks. Avalanche is a major threat in the higher altitude regions.”
The Chorabari lake burst triggered a devastating 2013 flash flood.
Three recent Kedarnath avalanches and others in the past came from the accumulation zone of the Companion Glacier.
Deposition zones of these avalanches are located 5 km uphill of the Kedarnath temple. The avalanche activity poses little or no threat to the temple township. Appreciable snowfall was experienced over high-altitude areas in September. The accumulation of heavy snow on top of the ridges facilitated avalanche events to the north of Kedarnath.
The report emphasized that “presence of several avalanche chutes in the accumulation zone of the Companion Glacier suggests that the glacier is mainly avalanche-fed and avalanches are common for that glacier.”