Introduction to the main project of Linhuaigang: The main project of Linhuaigang flood control is located in Huoqiu County, 28 kilometers above Zhengyangguan in the middle reaches of the main stream of the Huaihe River. It mainly includes 49 holes of shallow hole gates, 12 holes of deep hole gates, and 14 holes of Jiangtang Lake entrance. The flood gate, 500T Linhuaigang ship lock, upstream and downstream river diversions, main dam, auxiliary dam, etc. The project permanently covers an area of ​​19,200 acres and has a total length of 78 kilometers. It enjoys the reputation of "the world's first dam".