THIRUVANANTHAPURAM: The expert committee led by senior scientist John Mathai, appointed by the state government to examine the causes of landslides and make suggestions at Chooralmala and Mundakkai in Wayanad, has selected five areas suitable to establish the proposed township to rehabilitate survivors.
The two-part preliminary report submitted to the State Disaster Management Authority also ruled out human intervention as the cause for the July 30 landslides. The government had submitted a list of 20 places for building the township. After taking into consideration the soil structure, slope of the land, water bodies and the presence of swampy areas, the committee picked five places. It has ruled out any type of habitation at Punchirimattom. However, it also found safe areas at Chooralmala and Mundakkai.
The findings said the landslide occurred deep inside the forest area at a height of about 1,600 metres. “Within two days 572 mm rainfall happened as per the rain gauge station at Kalladi. The day before the landslide, there was 372 mm rainfall and on the day of the disaster, 200 mm. All the rainwater flowed to a central point on a concave slope and the landslide occurred from its flanks. Timber, trees, huge stones and other debris flowed through the Punnapuzha, a small stream. However, at two points, the debris with trees and rocks accumulated, interrupting the flow by creating a damming effect. The water level rose to 20-25 m at these two sites and ultimately broke down due to high pressure causing a strong downflow of flood water destroying the houses and buildings on the banks,” the report said.
“This has caused extreme devastation,” John Mathai told TNIE. “Normally, the debris would flow up to half a kilometre. However, due to the damming effect and subsequent breakage high volume of flood water all the debris flowed down and destroyed houses at Punchirimattom, Chooralmala and Mundakkai. At Chooralmala, there was a land formation from the sand that flowed down through years. People inhabited the area by building houses. It was densely populated. This land area was completely washed away with people that night,” he said.
The first part of the report identifies safe and unsafe areas in Mundakkai and Chooralmala, the second deals with the selection of township and rehabilitation process. John Mathai also dismissed the effect of quarrying as the cause of the landslide.
“In fact, there are no quarries in the 15-km radius around the landslide area. Climate change is the main reason behind the landslides. We have to address the issues of climate change post the 2018 flood,” he said.
