[Photo by Wu Huang/For China Daily]

Follow-up studies are continuing.

"It is not enough to get a panorama that relies only on field research of its layout and appearance," Liu said.

"For example, in-depth research on intersecting surfaces collected from two dams is ongoing. It will decode specific piling methods. And information about people's daily lives, which is hidden in the sediment, will be analyzed."

Liangzhu relics, first found in 1936, provide evidence of a sophisticated civilization lasting from 3300 BC to 2000 BC. The area is best known for its abundant jade.

"The world's water-management relics from roughly the same period of history that have been unearthed are mostly in arid areas such as ancient Egypt or Mesopotamia," Yu said. "But Liangzhu is on a humid southern bank of the Yangtze River, which is an unprecedented example."

However, there are still many unsolved puzzles.

"The age of the dams is basically indisputable now, but their function is still being debated among scholars," said Luan Fengshi, a professor from Shandong University.

"Basically, we don't believe it is likely that they were used for irrigation," Luan said. "Details of their construction and abandonment are yet to be confirmed."

Xu Xiaomin in Shanghai contributed to this story.