In 2018, southwest monsoon unleashed floods and landslides in Kerala, the magnitude of which has rarely been witnessed in recent past. The situation is considered similar to the violent floods of 1924 if not as serious. The Centre and state administration along with the armed forces worked hand-in-hand across all 14 districts to rescue thousands stranded in their homes.
According to the India Meteorological Department, from June 1 to August 16, 2018, Kerala received cumulative rainfall of 2227.26 mm, projecting an excess of 37.49 per cent rainfall in the 2018 monsoon. A normal course of monsoon is in the range of +/-19 per cent, thus signifying that this has been an extraordinary monsoon for the state. Idukki in central Kerala, a hilly terrain, received an excess rainfall of 83.59 per cent. Six other districts, Ernakulam, Palakkad, Thiruvananthapuram, Kollam, Kottayam and Malappuram all recorded excess rainfall of over 40 per cent from normal course.Twelve out of 14 districts in the state were on high alert, with the central and northern districts among the most affected. Particularly, the hilly districts of Idukki and Wayanad contributed the most casualties due to multiple landslips.
A total of 37 out of the states 42 dams and reservoirs had to be opened to drain out excess water from the catchment areas. Shutters of dams like Cheruthoni, one of the largest arch dams on the sub continent, were opened for the first time in 26 years, releasing lakhs of litres into the Periyar.