Kerala has been hit hard by heavy rains which claimed as many as 20 lives in the state, leaving a trail of destruction across the southern state. The water levels have risen in dams across the state and shutters of at least 22 reservoirs were opened to drain out excess water. Citizens have shared images and videos showing the destruction in the state. In a video that has emerged from Malappuram, a road can be seen crumbling as people stand and watch in fear. The video shared by CNN-News 18 on its Twitter handle shows a part of the road collapse as water flows past it. Minutes after that, another part of the road disintegrates creating a passage between the two parts of the road. Here is the video of the incident - #BREAKING | CNN-News18 #Exclusive | Dramatic visuals from Malappuram. Road crumbles in Kerala due to incessant rainfall. Watch the road cave-in at Malappuram in #Kerala. #KochiFloodThreat | @Neethureghu pic.twitter.com\/wAxDuoOpIx \u2014 News18 (@CNNnews18) August 9, 2018 The rain also forced the authorities to open a shutter of the Cheruthoni dam of the Idukki reservoir - considered the biggest arch dam in Asia - for the first time in 26 years. The step was taken after the water level touched 2,398.98 ft. The full reservoir level (FRL) of the dam is 2,403 ft. Chief Minister Pinarayi Vijayan said that the flood situation in the state was 'very grim' and also announced that the annual Nehru Trophy boat race, scheduled to be held at Punnamada Lake in Alappuzha district on August 11, has been postponed. "There is a possibility of water level increasing in Kuttanad in the district in the event of the Kakki reservoir lifting shutters. So, the boat race has been postponed. The new date will be announced later," Vijayan said. The government has sought assistance from Army, Navy and Coast Guard and six more columns of National Disaster Response Force (NDRF) had been requested to be deployed in the flood-hit areas.