The state of Kerala has been witnessing heavy rains with reservoirs at their full capacity and rivers overflowing for the past few days. Kerala's Pathanamthitta (in central Kerala) registered a maximum of 150 mm rainfall on Sunday, July 30 followed by Idukki and Kollam at around 100 mm.
In fact, as many as 46 people have been killed in rain-related incidents from July 29 to August 4 and over 6,400 people have been shifted to relief camps. But this is not the first time this is happening.
Why does the state witness extreme rain-related incidents year after year? What measures has the state taken to prevent further damage and loss?
What has been the history with Kerala rains?
The state witnessed extreme rainfall in 2018 which triggered the worst flood in the country in a century. There was an unusually high amount of rainfall that killed around 483 people and displaced many from their homes. As per the rainfall records of the Indian Meteorological Department (IMD), it has been found that the rainfall patterns recorded during August 2018 were comparable to the storm that occurred in the year 1924 in the state which is still fresh in the minds of many and is commonly referred to as the “Great Flood of 99” (as it occurred in the year 1099 according to the Malayalam Calendar). Although there are no official records from this period, reports point out that the death toll of the Great Flood of 99 is believed to be around 1,000.
In 2019, another spell of heavy rain drenched the state and left many houses crumbling and people scrambling to save their lives.
Why does this happen every year?
Researchers have attributed multiple reasons including the state’s location and geography, to these heavy torrential rains. A study published by researchers from the Indian Institute of Technology Bhubaneshwar, stated that a surge in moisture packet helped by the Arabian Sea monsoon flow, depression over the Bay of Bengal and features of the Western Ghats mountains triggered the torrential rains in the state in August 2018. In fact, similar conditions were responsible for the flood-like situation in the state in 2019 as well which killed 121 people. Another study conducted by the Cochin University of Science and Technology (CUSAT), Miami University, IMD and the Indian Institute of Tropical Meteorology said that the cloudburst (pattern of rain that causes heavy rain over a limited area) phenomenon causes regular floods in Kerala.
Additionally reports by the IMD have suggested that it is very hard to predict these cloudbursts due to its very small scale in space and time. They stated that a fine network of radars is required to be able to detect the likelihood of a cloudburst which could prove to be expensive. Meanwhile, a report by the Comptroller and Auditor General (CAG) in November 2021 revealed flaws in the management of the flood situation in the state, including the failure in issuing necessary alerts when the situation deteriorated, in 2018. The report shockingly pointed toward the mismanagement in flood preparedness of the state wherein there was a lack of real-time data on rainfall, water levels in important dams, and poor communication infrastructure in several dam sites.
What is different about it this year?
This year, the state is under the influence of at least three rainfall-triggering weather conditions. With strong westerly winds flowing in from the Arabian Sea, the presence of an east-west shear zone that is allowing monsoon winds to remain active and presence of a north-south trough running between Chhattisgarh and Comorin areas, is causing widespread rainfall in the state, according to weather reports.
A red alert was issued by the state yesterday, August 4 in eight districts (a red alert indicates heavy to extremely heavy rains of over 20 cm in 24 hours). Taking lessons from the bitter experience in 2018, the state has made multiple arrangements for relief for those who are affected. Those in areas where people were displaced during the 2018 floods, especially those in low-lying areas of Thrissur and Ernakulam districts, have been advised to move to camps.
What measures has the state taken?
The state has already deployed nine teams of the National Disaster Response Force (NDRF) in various areas. The Thrissur Collector has requested all those people who were asked to move out of their houses during the floods in 2018 and 2019 to vacate immediately, according to reports. The famous Sabarimala temple has now restricted entry to devotees. Additionally, the National Testing Agency (NTA) has postponed the Common University Entrance Test Undergraduate (CUET UG) 2022 exam in the state, which will now be held from tomorrow, August 6. Reports have also pointed out that a total of 14 relief camps have been set up in the state. The government has also cautioned people against the spread of various contagious diseases and has issued directives to prevent the same.