According to legend, more than 4,000 years ago, Xia Yu, the founder of China's flood control, was ordered by Emperor Shun Yao Chonghua to control floods in Taihu Lake. He dug three main waterways, Dongjiang River, Loujiang River and Wusong River, connecting Taihu Lake with the sea and diverting floodwaters into the sea. This is what Sima Qian recorded in "Records of the Grand Historian": "Yu controlled floods in Wu and connected three rivers and five lakes." Taihu Lake is vast, 200 miles from east to west and 120 miles from north to south, covering an area of 36,000 hectares.