Have a great article or blog to share?

Wayanad Landslide: How two villages vanished overnight

In the early hours of July 30, 2024, Chooralmala and Mundakkai villages in the district of Wayanad in Kerala were hit by a devastating landslide triggered by a torrential downpour. The massive landslide so far has claimed over 230 lives. According to the district administration, over 130 people are still missing as of August 13. This is the worst natural disaster to occurr in the State since the 2018 floods.

Chooralmala and Mundakkai, both located in Meppadi panchayat, are nearly 50km away from the district headquarters in Kalpetta. They were known for its scenic landscapes and waterfalls. Mundakkai is just 2.3km away from Chooralmala town by road.

Following the incident, the authorities launched a massive rescue operation in the area to look for possible survivors. A combined rescue mission of the Indian Army, National Disaster Response Force (NDRF), Fire and Rescue Force, Forest and Wildlife Force, and the police, along with hundreds of volunteers and government officials rescued several stranded people in the surrounding forest area and mud-filled locations. On August 1, Chief Minister Pinarayi Vijayan said over 9,300 people were staying in 91 relief camps in the district.

Landslide hit Mundakkai-Chooralmala region.

Landslide hit Mundakkai-Chooralmala region.
| Photo Credit:
Special arrangement

Now the search has entered its final phase. A 190-member team comprising NDRF, the police, Fire and Rescue Services, the Civil Defence Force, the Forest department, and rescue volunteers is engaged in the search for missing people in five zones of the disaster-struck area. The search mission had to stop several times due to heavy rains in the last two weeks and also when Prime Minister Narendra Modi visited the villages on August 10, 2024.

Areas hit by the landslide

The origin of the landslide has been identified as a valley above Punchirimattom, near the Mundakkai region. According to the satellite imagery released by ISRO’s National Remote Sensing Centre (NRSC), the “crown of the landslide” or the origin is above 1,550m above Mean Sea Level (MSL) and the approximate size of the main scarp is 86,000 sq m — roughly equivalent to 12 football fields.

The debri has traveled about 8 kilometers along the Iruvaniphuza River, altering its course, causing breaches in the banks, and destroying buildings and homes along the riverbanks.

photo-slider visualization

The images, captured by the Cartosat-3 and RISAT satellites, also show the before and after conditions of the affected areas. The pre-event images were taken by Cartosat-3 on May 22, 2023, while the post-event images were captured by the RISAT satellite on July 31, 2024. The pre-event image also shows an earlier landslide at the crown zone.

photo-slider visualization

Mundakkai and Punchirimattom areas

photo-slider visualization

The NRSC report reveals that torrential rains in the region triggered a massive debris flow, which intensified the landslide. The devastation was severe, with entire villages flattened.

Chooralmala area

photo-slider visualization

The trigger

The cause and various factors that have contributed to the intensity of the disaster are yet to be ascertained. However, the reports of post-disaster studies conducted by Kerala hold human-induced activities chiefly responsible for the increased intensity of landslides, although they point to excessive rains as the common trigger factor for the disaster.

Since June 22, the area has been subjected to nearly continuous rainfall, with only short breaks. On days before the incident, Mundakkai had received 572mm of rainfall in 48 hours – 200mm of rainfall in the first 24 hours and a massive 372 mm in the next 24 hours. Several other nearby places also received excessive rains on the previous day.

table visualization

This year, Wayanad received 15% less rainfall than the amount predicted by the IMD, that is, it received a total of 1,350 mm of rainfall from June 1, up until July 30. Out of this, the district received over 10% of the cumulative rainfall on a single day, which is, from 8.30 a.m. on July 29 to 8.30 a.m. on July 30.

chart visualization

Kalladi, about 5 km from Mundakkai, has recorded around 1,830 mm of rainfall in 30 days, making it one of the wettest areas in Wayanad.

This excessive rainfall played a crucial role in the disaster. A rapid analysis by World Weather Attribution, an international collaboration of scientists who analyse the influence of climate change on extreme weather events, has found the role of the climate crisis and change in land-use patterns over the years as trigger to the landslide.

Also read: Agriculture department to take a closer look at farming methods in Western Ghats regions

The study, released on August 14, 2024, also found that single-day monsoon downpours in Wayanad have become 10% heavier because of climate change.

The images slider below consists of aerial images taken of Chooralmala sourced from Google Earth Pro, 10 years apart. The first, which has visibly fewer establishments, was taken in March 2014, and the second in April 2024. In the highlighted areas, it is evident that there have been a rise in the number of residential, commercial, or other establishments in the area.

Kerala tops in landslides

Between 2015 and July 2022, as many as 3,782 significant landslides were reported in the country, with Kerala accounting for 2,239 of these incidents — nearly 60% — according to the Geological Survey of India and a statement made by Dr. Jitendra Singh, then Minister of State (Independent Charge) for the Ministry of Science and Technology and Earth Sciences, on July 27, 2022.

Wayanad: Highly susceptible to landslides

According to the Indian Landslide Susceptibility Map developed by the Hydrosense Lab at the Indian Institute of Technology in Delhi, over 31% of Wayanad’s land is classified as very highly susceptible to landslides. Among Kerala’s districts, Wayanad ranks first in terms of the proportion of land at very high risk of landslides. The graphic below shows the districts in the state that are highly and very highly susceptible to landslides, along with the approximate location of the landslides that occurred on July 30.

map visualization

One of the most fatal landslides in India

With over 230 people confirmed dead, the landslides in Wayanad on July 30 find their place among some of the most fatal landslides to have occurred. The timeline compiled below shows a list of landslide incidents in the country.

timeline visualization

Prepared by Gautam Doshi, Rhea Gupta, and Ramesh Rama Chandran

Source link

Share it :

Leave a Reply

Your email address will not be published.