The 18m (59ft) sculpture by Dutch artist Florentijn Hofman disappeared around 19:00 local time on Wednesday, after the city saw days of heavy rainfall, the Taiwan-based Want China Times reports . Even though the duck weighs 1 tonne, and was sitting on a 10 tonne metal platform lashed to the riverbed with steel wires, it was easily dislodged by the storm. "The duck flopped over and was flushed away really quickly by the torrential flood," exhibition co-ordinator Yan Jianxin tells the Wall Street Journal's China Real Time blog . "It disappeared right in front of me."