The Yongding River, also known as the Zhishui River, the Leishui River, the Sanggan River, the Lugou River, the Hunhe River, and the Wuding River, is one of the seven major river systems in the Haihe River Basin. It flows through three provinces，Inner Mongolia, Shanxi, Hebei, two municipalities，Beijing, Tianjin, and 43 counties and cities, and meets with the North Canal at Qujiadian. Part of the flood flows into the North Canal and then into the Haihe River, while most of the flood flows into the Yongding Xinhe River and enters the Bohai Sea at the Beitang Subdistrict, Tianjin. The river has a total length of 747 kilometers and an average slope of 2.85%. Its total drainage area is 47,000 square kilometers.
Its upper reaches flow through the Loess Plateau, with a high sediment content, so it is also known as the “Little Yellow River” and “the Hunhe River”. In its lower reaches, the riverbed has been filled with sediment, forming a river above ground, and it meanders unpredictably, so it was once called the “Wuding River”. From the 1950s to the 1960s, three large reservoirs (with a total reservoir capacity of 2.966 billion cubic meters) were built upstream, namely, Cetian, Youyi, and Guanting reservoir to control the drainage area of 43,402 square kilometers. In the lower reaches, the floodplain of Yongding River and Sanjiaodian were set up to flood storage and detention, and the Yongding New River was dug to discharge water into the sea port, basically solving the flood problem.
There are many legends about the Yongding River spread by people in the Yongding River Basin. These legends are connected with historical facts, reflecting the shadow of the history. Among these legends, one of the most representative is the Legend of Liu Niang Mansion. Legends of the Yongding River are vivid and rich in content, featuring a strong local color, and become the crystallization of wisdom of people on both sides of the river. It records the history of the people’s efforts to manage the Yongding River and provides detailed information for people to study the history of production development in Beijing.
The Yongding River not only nourishes the land and people along its banks, but also serves as a witness to the historical changes and cultural development of Beijing. As the mother river of Beijing, it carries the memories and emotions of Beijingers and is an indispensable part of the city.