Joshimath Land Subsidence Case A lesson for the Himalayan Cities

Jan interim compensation of `1.50 lakh per family with the assurance of further relief. Meanwhile, news of cracks in houses started coming from Karnaprayag and Chamba as well.

Joshimath is a typical small town in Uttarakhand with a population of just about 25,000 (16,709, as per Census 2011). However, it is prominent as the gateway for further travel to the holy shrines of Badrinath temple and Hemkunt Sahib, besides to the globally famous Auli Skiing Resort and the Valley of Flowers, a world heritage site. Therefore, it attracts a lot of transit visitors. According to State Tourism Department data, in 2021, over 1,65,000 people visited Joshimath town. However, more than half a million tourists went through the town to visit the surrounding famous destinations. Some houses in Joshimath started reporting cracks since early 2022, though there were sporadic cases even earlier too. Since early January 2023, more houses started developing cracks and the number reached close to 600 by January 12. Cracks had appeared in the roads also. The Government of Uttarakhand started shifting people from the cracked houses to safer buildings and also announced

The reason behind this situation was subsidence (sinking) of the land. On January 13, 2023, ISRO’s National Remote Sensing Centre (NRSC) reported that their satellite imagery had indicated that Joshimath had sunk by 5.4 cms in just 12 days. The subsidence was preceded by and coincided with water gushing out from beneath the earth at various locations.

Land subsidence is noticed in many cities across the world, most notable being Tianjin, China (5.22 cm per year), Semarang, Indonesia (3.96), Jakarta, Indonesia (3.44), Shanghai, China (2.94), etc. Most of these are coastal cities and face subsidence mainly owing to the soil conditions, besides depletion of the subsoil aquifers due to largescale evacuation through borewells for meeting the water needs.

The situation of the sinking in Himalayan towns is somewhat different. The area is geologically unstable and sloping, resulting in landslides. Many such towns, like Joshimath, have come up on the debris of past landslides, resulting in poor load-bearing capacity of the soil. These towns are in seismic zone as well.

These factors call for very frugal level of construction activity. However, RCCbased building construction activities including those having multiple floors, have become popular in the Himalayan region. Such structures induce or accelerate subsidence.

These towns generally have poor drainage system, leading to water seepage, which further weakens the soil. Himalayan region also has widespread prevalence of subsoil water aquifers, embedded precariously amidst relatively loose soils. Blasting activities, which is resorted for clearing boulders, tend to create fractures in the aquifers. Any other means adopted for removal of boulders too leads to the same results. For instance, tunnel boring or drilling for borewells could lead to puncturing the aquifers. The water that gushes out of the aquifers loosens the soil on the surface and the seepage accentuates the instability of the soil beneath. Deforestation is yet another cause for weakening of the soil.

Largescale hydroelectric power generation projects in the Himalayan region induce instability in the land structure of the region, leading, inter alia, to land subsidence. There are concerns that the NTPC’s Tapovan–Vishnugad Hydroelectric Project located close to Joshimath could be a major culprit for the subsidence issue.

Various National and State Highways have been upgraded from time to time, by way of widening of the carriageway. The length of roads in Uttarakhand was reported at 52,848 km for 2018 and increased to 68,727 km in 2019. In the process of road development, mountains are cut by removing boulders and the adjoining soils and debris using detonators which destabilises the mountain slopes and makes them vulnerable to landslides. Construction of retention walls mitigates this problem, but does not resolve it fully and during heavy rains, the retention walls give way to the flowing slurry of debris.

THe wAy FORwARD

The Himalayan region is becoming popular with tourists for its pristine beauty and adventure sports. Recent reports indicate that as many as 10 crore tourists visited Uttarakhand during 2022 alone! The State and its local bodies welcome visitors with open arms, in the hope of economic gains. However, the experience of the last 75 years has clearly indicated that the strategy for development and management of the Himalayan region cannot be the same as for the other parts of the country, owing to its fragile geology. Some suggestions for ensuring a sustainable growth and development of the Himalayan cities and towns are presented below.

Regional and Local Planning

The state needs to have a 3-tier planning framework, starting with an overarching Development Planning Strategy for the state as a whole based on the core principles indicated under the National Mission for Sustaining the Himalayan ecosystem. At the second and third levels, Regional and Local Plans should be prepared. The Local Plans should be microzonation-based with relevant local data and studies. These plans should be vertically integrated and made applicable to all departments/sectors/projects of all State and Central Government Agencies.

Building By-laws

The Building By-Laws 2011 (BBL) need to be revisited, to ensure alignment of its provisions with the Regional and Local Plans. For instance, if a particular piece of land falls in subsidence zone or seismic zone of different levels, the BBL should prescribe specific construction and development norms.

Restriction on the visitors’ numbers

The surging numbers of visitors is detrimental to the sustainability of the Himalayan region. It is necessary to restrict the number of visitors to the various tourism locations. Switzerland, a hill country, has not agreed to host any Olympic Games since 1948, due to its negative impact.

eco-friendly housing

Rather than adopting the RCC structures for housing, the Himalayan Region would be advised to go for light weight earthquake- resilient construction. For example, the Light Gauge Steel Frame

Structure, where cold-formed steel is used as the primary construction material.

Tree plantation

Deforestation around habitats in hill areas leads to loosening of the soil making it prone to landslides. Therefore, it is necessary to launch tree-planting in and around the towns in Himalayas.

Drainage and sewerage network

Inadequate drainage and sewerage systems are a common feature in most of the smaller and medium towns of the Himalayan Region. Thus, the waste water and the storm water are unable to flow out smoothly, leading to stagnation, which adds to the environment risks of soil subsidence. each Town and Local Area needs to develop drainage and sewerage plans, in line with the Regional and the State Plans.

Collaborative Governance

The Uttarakhand Urban Planning & Development Act 1973 provides exemption to the Central Government’s Projects from its applicability. Therefore, the major projects of the Central Government, such as the National Highways, or the large hydro-electric projects, do not get scrutinised by the Town Planning and other relevant departments of the State Government. It would be desirable to provide joint ownership and control to the Central and State Government for such large projects, on the lines of the Metro Rail Companies of Delhi, Bengaluru, Chennai etc.

Strengthening of Local Govt

Many Himalayan Towns have quite small resident population but are host to large floating and visiting population. For instance, Joshimath has a Census population of around 20,000, whereas it receives over 5 lakh visitors every year. However, the staffing pattern of the local bodies and agencies is determined largely based on the resident population. This situation needs a review.

[The views expressed are the author’s own. They do not purport to reflect the views of Urban Update.]