The retreat and return of Gucheng Lake opened the construction curtain

Recently, in the vast area of the levee on the north bank of Gucheng Lake, Nanjing's largest project to return water to the lake began construction. As an important water storage and regulation lake in the lower reaches of the Yangtze River, Gucheng Lake will expand its water surface by 6.11 square kilometers, which is equivalent to adding 4.5 Xuanwu Lakes in water volume and 1 West Lake in area.

The reporter drove along the north bank of Gucheng Lake stretching several kilometers of green enclosure, enclosure inside reeds, ridge throughout, dozens of machinery to come and go, here is the site of the retreat Wei lake project. It is understood that the water area of Gucheng Lake reached 78 square kilometers more than 50 years ago. From the 1960s to the 1980s, in order to ensure food supply, the local implementation of lake beach reclamation. After historical evolution, the area of the lake area has gradually shrunk to 31.99 square kilometers today, less than half of that time, and its water storage capacity, water mobility and water quality have been reduced.

Song Deyu, head of the project management team of Gaochun Construction and Development Group, said that due to the development of polders, the north side of Gucheng Lake has been compressed into a "calabash mouth", forming two large and small lakes. The Gucheng Lake seen in Lakeside square of Gaochun main city is a small lake on the west side, and the scenic belt around the lake is mainly concentrated here. The retreat of the lake is to push the water northward, thus opening the "gourd mouth", so that Gucheng Lake as a whole. This time, 9,821 people from 10 local villages and more than 5 million square meters of crab farming area were involved. After the acquisition of land and attachments, the project was completed in December last year.

The person in charge of the project of China Railway Construction Engineering, the construction unit, introduced that in accordance with the restoration requirements of the lake area, the elevation of the lake bottom should be eliminated downward by 0.8-1 meters. Reporter's eyes and areas, roads, dikes, mounds and so on are to be excavated. The excavated earth will be used to build six ecological islands in the lake in the future. "The polder area is a paradise for birds, and after it becomes a lake area, the ecological islands will become a new habitat for birds."

The reporter then drove to the northernmost point of the Tuiwei Lake project, according to the introduction, here is the future of the new lake dam. The entire length of the 6.2km dam is filled with loess, each 30 cm thick in one layer, rolled through nine processes, and then filled in the second layer, and so on, until the height of the dam is raised to 14.5 meters, which is nearly 2 meters higher than the highest flood level of Gucheng Lake this year.

Song Deyu told reporters that the first phase of the dam will be filled with 2.16 million cubic meters of soil, while the entire project will require earthwork of 8 million cubic meters. Such a huge excavation and filling project, the site used more than 100 machines 24 hours a day shift construction. The project is expected to be completed by the end of 2022, and Gucheng Lake will increase from 31.99 square kilometers to 38.4 square kilometers, with an effective flood control storage capacity of 22 million cubic meters restored.

Gucheng Lake Return-to-lake project is one of the national pilot projects.  After the completion of the project, the Taihu Lake, Yangtze River two major basin to improve water quality, eliminate flood will play a great role in promoting. On the north bank of the new Lake District is the planned riverside science and technology New town of Gaochun. Tuiwei Lake returning in the north and the cross-lake bridge under construction in the south will change the local urban form and ecological pattern, usher in the lake-hugging development era of Gaochun, and build an ecological livable demonstration area.

Article source: Nanjing Daily