Encountering the Grand Canal │ The Technological Wisdom that Flows for Thousands of Years

Nurturing for thousands of years, the Grand Canal stretches for thousands of miles in a winding manner. As a great water conservancy project in human history, the Grand Canal embodies the remarkable wisdom of generations of working people.

"The successful application of the Grand Canal for World Heritage status is largely attributed to the technological wisdom of two key water conservancy projects: Beinanwang and Qingkou. One is known as the 'Water Ridge of the Canal', and the other is known as the 'Throat of the Canal'," said Zhang Jin, a member of the expert database of the National Cultural Heritage Administration and the chief writer of the text for the application of the Grand Canal for World Heritage status.

The Beinanwang Hub is located at the highest point of the Grand Canal, earning it the nickname "Water Ridge of the Canal". How to make water flow uphill was a difficulty that had to be overcome for the Grand Canal to cross this high point and achieve full-line connectivity.

The responsibility of solving this difficulty fell on Song Li, the Minister of Works at that time. He adopted the suggestion of Bai Ying, a local folk water conservancy expert, of "drawing water from the Wen River to supplement the canal," which cleverly solved the water source problem of the "Water Ridge of the Canal." At the T-junction where the Xiaowen River meets the canal, craftsmen constructed stone revetments to reduce the impact of the Wen River's waters, and then built a fishback-shaped stone weir at the bottom of the river, using the weir to divert the Wen River's waters north and south, achieving a reasonable diversion of "seven parts going towards the emperor and three parts going down to the south."

The completion of the Beinanwang Hub played a significant role in the economic prosperity of the Ming and Qing dynasties. "The Daicun Dam and the Beinanwang Hub together ensured the smooth transportation of grain supplies for more than 500 years, and the carrying capacity of the Grand Canal was thus increased by ten times."

The Qingkou Hub is another hub project on the Grand Canal with high technological content. During the Ming and Qing dynasties, the Canal, Yellow River, and Huai River converged in Huaian. The high water level of the Yellow River easily caused backflow into the Huai River and the Canal, leading to riverbed silting. This resulted in unfavorable navigation at best and frequent floods at worst. To address the issue of governance and transportation at the confluence of the three rivers, a large-scale Qingkou Water Conservancy Hub was built.

"The biggest contributor here was Pan Jixun. In the past, river management involved either diverting water or widening the riverbed, but Pan Jixun did the opposite. He narrowed the riverbed, utilizing the force of the water to carry away the sediment," explained Zhang Jin figuratively. "Hongze Lake actually serves as a 'kettle,' and the spout is crucial. With several spouts flushing together, the clear water of Hongze Lake is lifted up and then flows into the Canal, constricting the water to attack the sand. This is how the task of storing clear water to flush away the yellow sediment and using constricted water to attack the sand was accomplished."

The ancient project shines with the wisdom of the Grand Canal's water conservancy. Along with the flow of the river, the dialogue between humans and nature has continued, crystallizing into new wisdom embodied by the largest aquatic interchange project in Asia, located in Huaian. Here, the Huai River and the Grand Canal each follow their own paths without interference from each other. Through the staggered approach of constructing a canal aqueduct above and a drainage culvert below, a vertical three-dimensional intersection of the Huai River and the Beijing-Hangzhou Grand Canal is achieved. The Grand Canal above does not affect navigation, and the Huai River's waterway to the sea below does not affect flood drainage.

"This is a handshake between a two-thousand-year-old ancient project and a modern project," said Shan Jixiang, President of the China Cultural Relics Society and Director of the Academic Committee of the Forbidden City. He also believes that this demonstrates that the Grand Canal is a river with a lifecycle. "It is not frozen in a single era. It spans various eras, up to our contemporary and modern times, and has been continuously improved."

With the relay of generations of people, the Grand Canal flows forward, and the water conservancy wisdom and technological wisdom contained within have been inherited across thousands of years. Zhang Jin introduced, "The natural and geographical conditions in the area where the China Grand Canal is located are extremely complex. Numerous representative water conservancy projects emerged during the excavation and construction