Joshimath: Fears of aggravation in land subsidence over upcoming monsoon season

With the impending monsoon season in Uttarakhand, locals and experts alike have raised concerns over aggravation in land subsidence in Joshimath town fearing water could percolate deep into the fissures and cracked houses.

Uttarakhand usually witnesses high average annual rainfall of 1162.7 mm with Chamoli reporting 1230.8 mm annual rainfall.

During last year’s monsoon when the state received 1128 mm rainfall (June -September), Chamoli was one of the two districts among the state’s 13 districts, which received the highest rainfall.

Chamoli received 1196.4 mm of rainfall.

Rain normally arrives in the state on late April and continues up to September, with the intensity increasing during the months of June to September.

Also Read: Joshimath crisis is due to landslide, not subsidence: Experts

As a larger part of Chamoli district is situated on the southern slopes of the outer Himalayas, monsoon currents penetrate through trenched valleys, with rainfall reaching its maximum in the monsoon season spanning between June to September.

Chamoli district, where Joshimath falls, has a history of extreme rainfall events, with Indian Meteorological Department (IMD) rainfall data stating Chamoli received 537.9 mm rainfall in July 2013, which was the second highest recorded rainfall in the district since 1901-2000 and 2008-2013.

The maximum rainfall of 860.7 mm in the 100-year period was reported in September 1924.

Nain Singh Bhandari, president of Joshimath Vyapar Mandal, said, “The administration report says the cracks have stopped appearing in houses and fields, but the situation is otherwise in our town. They are wasting time suppressing reality, rather than addressing the problem. In monsoon season, the situation will deteriorate if the town receives heavy rainfall.”

Digambar Rawat, an affected member who lives in a relief camp set up by the administration at the Nagar Palika Parishad building, said, “Now the administration has declared many houses which were earlier termed unsafe as livable. If the affected people continue to live in badly damaged houses, their life will be under threat, especially during the upcoming monsoon.”

Atul Sati, convenor of Joshimath Bachao Sangharsh Samiti (JBSS), said, “The situation in monsoon will aggravate due to continuous rain. As happened recently, new cracks may appear and the current ones will get bigger and deeper in the monsoon season. The administration had filled the cracks with soil before the rains recently. But their plan failed miserably. The administration doesn’t seem to be serious about tackling the monsoon challenge. We demand the authorities declare complete Joshimath as land subsidence affected and shift everyone to safer areas.”

YP Sundriyal, a geologist from HNB Garhwal University, Srinagar said the monsoon rains will further destabilise the terrain of Joshimath with both vertical and horizontal movement of rainwater.

“When water will percolate into the ground fissures and accumulate, we don’t know how much pressure it will develop within the unstable ground. As these fissures cannot be plugged in, the best thing for the government is to shift all people to safer locations. The monsoon rains can aggravate Joshimath’s subsidence, and the government needs to be vigilant about the situation”, he said.

Another geologist SP Sati from Veer Chandra Singh Garhwali Uttarakhand University of Horticulture and Forestry said that over 4,000 structures are located on the ancient landslide material in Joshimath, heavy monsoon rains in the area when the cracks and ground fissures have widened since last year can cause further instability in the area.

“The best strategy at present is to save people and shift them to safer locations. Water seepage into fractured geological terrain can aggravate land subsidence in Joshimath and we don’t know how it will affect the whole landmass there”, he said.

The monsoon rains can also fluctuate water levels in rivers in the area.

Rivers in Chamoli district (Alaknanda, Saraswati, Dhauli Ganga, Birhi Ganga, Rishi Ganga, Kail, Pindar, Nandakini) generally flow with great force in steep and narrow channels often resulting in excessive erosion and collapse of the banks.

This was also witnessed during February 2021 Chamoli tragedy when a glacial debris outburst, eroded the banks of the Alaknanda river flowing beneath the Joshimath town, with experts saying it is likely one of the contributing factors for land subsidence.

The February 2021 Chamoli tragedy near Raini village, which is just 20km from Joshimath, show how vulnerable the area is to disasters.

On February 7, 2021, the slope on which Raini village stands suffered great damage on account of flash floods that damaged two under-construction hydel power projects - Rishi Ganga and NTPC’s Tapovan Dam- killing 204 persons, with only 92 bodies recovered so far.

Raini was again hit by floods following incessant rainfall between June 13 and 17.

Joshimath residents say the crisis in the town is connected to the 2021 tragedy.

Atul Sati, a local activist and convenor of the Joshimath Bachao Sangharsh Samiti, claimed it is after the 2021 floods that cracks started appearing in people’s homes, as flash flood eroding toe of the Alaknanda river, flowing at the base of the Joshimath town.

The possibility of an earthquake further establishing Joshimath’s fragile geology is also worrying locals, as Uttarakhand reports high seismic activity, with most areas falling under Seismic Zones IV and V.

Owing to its proximity to main central thrust (MCT) which is the most active seismic zone, Chamoli is vulnerable to different kinds of hazards such as landslides, avalanches, glacial lake outburst flood (GLOF), landslide lake outburst floods (LLOF), cloud bursts, debris flow, flash floods, earthquakes.

Just last month, two earthquakes hit the state - one measuring 2.5 on the Richter scale in Bageshwar district and another 2.8 Richter scale in Pithoragarh.

On December 8, 2019, the Joshimath area was hit by an earthquake measuring 3.2 on the Richter scale.

In September 2019, an earthquake measuring 3.6 on the Richter scale was also reported from Chamoli district.

A 6.8 magnitude earthquake hit Chamoli in March 1999, killing over 100 people and damaging buildings across the area

Hemant Dhyani, noted environmentalist and member of the Supreme Court-appointed high powered committee (HPC) on Char Dham Project said it is not just the rains that can be dangerous, but seismic activity, with the state reporting over a dozen earthquakes in the last one year, can also aggravate land subsidence in Joshimath.

“We should not forget the 1999 earthquake that hit Chamoli, which killed over 100 people. Government has to keep in mind all these issues while coming up with a rehabilitation plan for the affected people in Joshimath. Also, the government should not delay the rehabilitation process”

Ranjit Kumar Sinha, secretary disaster management department Uttarakhand government said the state government will take all possible measures for the safety of affected people in Joshimath.

“We are aware of the apprehensions that rainfall during the monsoon period might aggravate land subsidence in Joshimath. So, all possible measures will be taken to ensure the safety of the affected people”, he said.

According to Chamoli district administration, so far 868 structures have developed cracks in Joshimath, with 181 being declared unsafe. 878 persons have been shifted to safer locations.