Is it necessary to build a large reservoir in Mengyin Duozhuang?

Mengyin Duozhuang is to build a large reservoir. Yunmeng Lake covers an area of 4,200 hectares, located in the east of Mengyin County, Linyi City, Shandong Province, at 15 km, with a storage capacity of 782 million cubic meters, a dam height of 29.8 meters, a dam length of 1.665 meters, a drainage area of 1.60 hectares and an irrigation area of 1.07 million hectares.