Two out of the three houses in Joshimath are reeling from the impact of land subsidence, reveals a new report that details the losses, which were visible in images of cracks across the hill town earlier this year.
The report released by a National Disaster Management Authority (NDMA)-led panel has found that around 65 per cent of houses have been affected by incidents of land subsidence, resulting in damage to property worth Rs 565 crore.
In precise terms, a staggering 1,403 houses out of a total of 2,152 require immediate attention at the pilgrimage town in Uttarakhand.
The report was based on an analysis by a 35-member team that carried out a “post-disaster needs assessment” from April 22 to 25 to assess the damage and to identify the assistance required for the long-term recovery and reconstruction of the affected sites.
The team comprised professionals from the NDMA, United Nations agencies, CSIR-Central Building Research Institute, National Institute of Disaster Management, and other organisations. Business Standard has accessed a copy of the report, which classified the houses into different categories to assess the extent of damage.
The categories are defined as follows: Black (partially collapsed), red (unsafe and slated for demolition), yellow (requiring repairs or retrofitting), and green (deemed safe). Out of these, 472 buildings fall under the black and red segments, while 931 structures are categorised as yellow.
“Emphasising the ‘build back better’ approach, it’s crucial to enhance the resilience of partially damaged houses against landslides and other disasters,” the report said.
The total cost of reconstruction is projected to be Rs 422 crore, with 472 houses estimated at Rs 91 crore and another 931 pegged at Rs 331 crore.
The report attributed the primary causes of the damage to houses in Joshimath to weak building material, inadequate reinforcement, structural deficiencies, and the placing of structures on steep slopes. It emphasised that even minor ground subsidence resulted in extensive building damage due to the use of fragile mud-based mortar for binding bricks or stones.
The report also listed data provided by the local administration, according to which the initial discharge of silt-laden muddy water to the extent of 600 litre per minute on January 2, 2023, had reduced to 200 litre per minute on January 11. Currently, the discharge is almost none.
Despite the minimal discharge at present, the report advised the state government to implement a comprehensive ban on construction activities in the town until the end of the monsoon season. Following a post-monsoon assessment of ground conditions, it proposed allowing construction exclusively for lightweight structures.
This wasn’t the first occurrence of landslides in Joshimath. Instances of land subsidence were documented in the 1970s as well.
A panel set up under the chairmanship of Garhwal Commissioner Mahesh Chandra Mishra submitted a report in 1978, stating that major construction work should not be carried out in the town and in the Niti and Mana valleys as these areas are situated on moraines — a mass of rocks, sediment, and soil transported and deposited by a glacier.
In September 2022, a report by the Uttarakhand government observed that the hill town located at a height of 1,830 metres is sinking gradually since the beginning of last year itself.
The Himalayan town lies in seismic zone V (the region most vulnerable to earthquakes) and is prone to landslides and flash floods.