KOCHI: Waging a tough battle for six months against a virus that has brought the world to its knees, Kerala is set to face another gruelling task. An analysis by Tamil Nadu weatherman has triggered speculation that the state is bracing for yet another devastating flood. The repeated warning issued by the government on the possibility of torrential rain in August has created panic. Though meteorologists rebuff the theory, people living on the banks of rivers, who have learnt a hard lesson, are not ready to take chances. Many families living on the banks of Chalakudy river and Periyar in Aluva have taken houses on rent in safer places or booked hotel rooms in advance expecting a deluge.
“The memories of the 2018 flood devastation refuse to fade. Even two-storey houses were submerged and we lost all our belongings. We have learnt a hard lesson. Earlier there was only a couple of country boats in this area but now you can see more than a hundred fibre boats on both sides of Chalakudy river. I have shifted my belongings to the first floor of the house,” said Shaju Varghese, whose house is located close to the river in Chalakudy. Adding to the flood fear is the Covid anxiety. People are taking houses on rent foreseeing a scenario where they will be shifted to relief camps. “It is risky to live in a relief camp as the spread of Covid has put people under tremendous stress. People here are preferring rented houses due to Covid fear,” said Shaju.
But is it worth the panic? Even the Kerala State Disaster Management Authority does not see chances of torrential rain in August. “The IMD forecast only says there will be above normal rain from July 31 to August 13. Torrential rains cannot be predicted more than five days ahead. But we are not taking chances and have taken all precautionary steps as per the orange book (Standard operating procedure for emergency situation released by KSDMA). Review meetings have been held and the incident response system has been put in place.
Selected personnel have been given training by the National Disaster Management Authority,” said KSDMA member secretary Sekhar Lukose Kuriakose. Can we expect a repeat of 2018 and 2019 floods? The situation is entirely different, says IMD former director S Sudevan. “There is no scientific base for a forecast made two months in advance. The extended range forecast issued by the IMD says that the state may receive above-normal rain from July 31 to August 20. This means only 10 mm to 15 mm increase in rainfall. Torrential rain can be forecast only three days in advance, he said.
It is the depression in the Bay of Bengal and typhoons in the West Pacific Ocean near the Philippines that bring good rain to the Western Ghats. A low-pressure area is likely to form over North Bay of Bengal around August 4. This is the cause of the present active monsoon in Kerala. There are also indications of the formation of a low-pressure area over northwest Bay of Bengal towards August 13 also without much intensification probability. These two systems may bring more rain. But there is no possibility of an extreme climatic event like 2018 flood, said Sudevan.
There will be around five active phases during the southwest monsoon and this is the first time monsoon has become active this year, said Cusat Department of Atmospheric Sciences assistant professor S Abhilash. “In 2018, there was a depression in the Bay of Bengal and around three typhoons in the West Pacific Ocean caused torrential rain. In 2019 also, there were typhoons and the Indian Ocean Dipole was in a positive phase. But this time there are no typhoons in the Pacific and the Indian Ocean Dipole is neutral. There are chances of 4 to 10 cm rainfall above normal due to the impact of the low-pressure area in the Bay of Bengal,” he said.
Abhilash said even the cloud structure was entirely different in 2019. “The cloud was cumulonimbus in nature with dense, towering vertical cloud formation. The situation now is entirely different from 2018 and 2019. It is an active phase of monsoon and we can expect good rain, minor incidents of mudslide and waterlogging,” he said. Though we don’t expect torrential rain, we have to stay prepared to face an emergency situation considering the fact that flood relief during Covid outbreak is challenging, said earth scientist Subhash Chandra Bose.
“The government has identified around 3,000 shelters to rehabilitate people living on the banks of rivers in view of the forecast. But maintaining Covid protocol is a tough challenge. We have experience in managing flood situation but rehabilitating the elderly and children in relief camps and ensuring food and beds will be an arduous task. We are getting dry spells in between and these intervals should be used for cleaning work. There are large clusters in flood-prone areas and coastal areas and old age homes in such areas pose a tough challenge,” he said.
Are the dams safe? The fear of flood brings attention to the dams as the release of water from them had aggravated the situation in 2018. Almost all the 54 major dams in the state were opened between August 8 and 16 which led to the flooding of the coastal plains. Adding to the woes, the perigean spring tide in the sea stopped the floodwater from draining out. “Though there was a red alert in Idukki on July 30, we received only 20-25 mm rainfall. The water level in Idukki dam stands at 2,335 ft which is 45 ft below the crest level. Only Banasurasagar has got some good inflow.
There is no need for panic as there will not be any need to open the flood gates even if we receive heavy rain for a week,” said KSEB chairman N S Pillai. “We have opened the sand bund at Thottappally on Friday to drain out the floodwater. The width of the channel at the river mouth has been increased from 160 to 391m. The water storage in major dams stands at less than 70% and we have completed the mainte nance work of dam shutters. Satellite phones have been provided to dam chief engineers and they are filing three reports a day on the ground situation,” said Irrigation department chief engineer D Biju.
2018 flood
5th 2020 biggest flood in the world after 2015
Economic loss:
E31,000 cr People in relief camps: 1.5 million
ochi airport closed from August 15 to August 29
1/6th of total population directly affected
Flood gates of all major dams opened
331 landslides and 104 lives lost
1,11,356 houses in urban areas affected
6,92,848 houses in rural areas affected
96% Rainfall in Kerala in August 2018 was 96% above the long-term average
Idukki figures
Normal rain in August: 527.3 mm
August 2018: 1,478.9 mm
Rainfall in Kerala from August 1-19, 2018: 758.6 mm
Normal rainfall during the period: 287.6 mm
Peak spell August 8-17, 2018
Kerala received 414 mm rainfall from August 15-17
Nilambur received 398 mm rainfall on August 9, 2018
Runoff in rivers: 12 billion cubic metre
2019 FLOOD
Houses completely damaged: 1,967
Houses partially damaged: 19,297
Relief camps: 1,318
People in relief camps:2 lakh
123% excess rainfall
Peak rainfall August 6-14
Rainfall during the perio 602.2 mm
Normal rainfall during the period 122 mm
Departure
394%
2018 August 1-30 Normal rainfall: 419.3 mm | August 2018: 821 mm | Departure: +96%
2019 August 8-31: Deaths: 58 in Malappuram, 17 in Kozhikode, 12 in Wayanad | 42 injured