Land subsidence in Joshimath

(MainsGS3:Disaster and disaster management.)

Context:

Central government agencies and experts are assisting Uttarakhand to prepare short-, medium- and long-term plans to deal with the Joshimath situation.

Importance of Joshimath:

• At a height of 6,107 feet, Joshimath is a busy town in Chamoli district and despite a population of only about 23,000, it has been heavily built-on, with hotels, resorts, and a bustling market that caters mainly to tourists, pilgrims, trekkers and personnel of the army and the Indo-Tibetan Border Police (ITBP).
• After the 1962 India-China war, Joshimath emerged as a place of strategic importance as it leads to villages along the India-China border and is also en route to Barahoti, a disputed territory along the border. 
• The town is also a gateway to noted sites of pilgrimage – Badrinath for Hindus and Hemkund Sahib for Sikhs; the international skiing site of Auli; and the Valley of Flowers, a UNESCO World Heritage site.
• Today, Joshimath is overly burdened with structures built without any regard for the land’s load-bearing capacity.

Reasons for land subsidence:

• Joshimath’s geological setting, together with the unplanned and rampant construction in and around the town, have resulted in land subsidence.
• Joshimath is built on the deposits of an old landslide, which means the slopes can be destabilised even by slight triggers. 
• The town is also in Zone V, denoting highest risk, in India’s seismic zonation scheme. 
• It lies between two thrusts, the Main Central Thrust (MCT) and the Vaikrita Thrust (VT), and thus occupies a seismically active terrain.
• Joshimath is also prone to extreme weather as climatologically, Joshimath lies in a region that frequently receives high-intensity, focussed rainfall.
• Extreme rains, for example, could trigger landslides, since the slopes are precariously balanced.
• Joshimath is a deposit of sand and stone, hence was not a suitable place for the coming up of a township as vibrations produced by blasting and heavy traffic will also lead to disequilibrium in natural factors.

The NTPC’s role:Locals have blamed the NTPC’s 520-MW Tapovan Vishnugad hydropower project, under construction in the area, for exacerbating the Joshimath land subsidence. 

• On December 24, 2009, a tunnel boring machine punctured an aquifer some 3 km from Selang village, which is only about 5 km from Joshimath. 
• The tunnel is nearly a kilometre under Auli, near Joshimath. The puncture released water at 700-800 litres per second, enough to meet the needs of at least 2 million people every day.
• However, NTPC clarifies that there have been no scientific studies establishing links between the puncture and the subsidence in Joshimath.

Char Dham project:

• The 6-km Helang-Marwari bypass, being built by the Border Roads Organisation (BRO), is also under scrutiny for weakening slopes and further destabilising the local topography. 
• The bypass is part of the 825-km Char Dham highway expansion project in Uttarakhand, which experts have already questioned for unscientific slope-cutting, which resulted in several landslides.
• The 2022 USDMA report also pointed to a lack of drainage and wastewater disposal systems as being part of the subsidence problem as about 85% of buildings in the town – including those owned by the army – aren’t connected to a sewerage system and have soak pits instead.

Conclusion:

• The subsidence in Joshimath has captured the nation’s attention because it is a destination for both pilgrims and tourists, but it is far from being the site of the first or the deadliest incident. 
• The government must undertake whatever repair and restoration efforts it is undertaking at Joshimath at all the other sites as well.