Joshimath (or, Jyotirmath) town in Chamoli District of Uttarakhand state in India, which is located at an altitude of 1875 m on the foothills of the Himalayas is facing disaster like situation for some time. Hundreds of houses and hotels and roads in the town have developed cracks. Many buildings have been declared unsafe for human habitation and few are being pulled down.
The town is said to be ‘sinking’ due to uncontrolled building construction, highway and power plant development in the area are said to be reasons behind the problem. Based on satellite imagery, it has been suggested that the town sank at a fast rate (5.4 cm in just 12 days) between December 27, 2022 and January 8, 2023 compared to a slower rate (about 9 cm in 7 months) between April and November 2022. It is suspected that the entire town may sink and the Joshimath-Auli road may collapse.
However, it looks like that the town of Joshimath is actually sliding down the Himalayan ridge. It is NOT a case of sinking or land subsidence.
It is known for some time that the town is located on the site of an ancient landslide along a running Himalayan ridge.
As per an American Geophysical Union blog published on January 23 by Dave Petley of the University of Hull, Joshimath crisis is a case of ‘’land mass slipping down the slope”. He says, “Google Earth imagery clearly demonstrates that the town is built on an ancient landslide.”
It is sliding down the slope that has led to cracks in the buildings. Subsidence, which is vertical downward movement is not applicable in the case of Joshimath.
Google Earth imagery clearly show that the town is situated on a slope along a down ward Himalayan ridge on an ancient stabilized moraine landslide debris which attained maturity with time.
A more detailed investigation along this line is needed.