Geography of Beijing - Hydrology

Hydrology

Several major rivers, including the Yongding, Chaobai and Wenyu flow through Beijing Municipality. They originate on the Inner Mongolia Plateau, cut through the mountains west and north of the city, and eventually empty into the Bohai Sea. Today, no major river flows through the city itself. Over the centuries, the builders of Beijing have managed to steer the rivers around the city. Thanks to man-made lakes, channels, moats and aqueducts, these rivers continue to provide water to the city and drain its refuse, but they no longer threaten Beijing with flooding.

Downtown Beijing has several lakes called hai or sea. During the Yuan Dynasty, the Mongol rulers expanded them and built imperial palace of Dadu around them. Subsequent emperors of the Ming and Qing dynasties used the lakes as imperial gardens. Today, the three northernmost lakes, Xihai (West Sea), Houhai (Rear Sea) and Qianhai (Front Sea), collectively known as Shichahai, are lined with bars and cafés and known for nightlife. To their south, Beihai (North Sea) is a city park, and Zhonghai (Central Sea) and Nanhai (South Sea) are part of the Zhongnanhai Compound, residence to China's leaders. This string of lakes used to form the main riverbed of the Yongding River, which now flows 50–60 km to the west. But 1,800 years ago, the Yongding flowed through Jishuitan and downtown Beijing and then into Longtan Lake and on to Tongzhou. A major flood in 295 A.D. devastated part of Beijing, then known as Ji. Just west of Wangfujing, there is still a stretch of Beijing called Shatan or Sandy Beach.

Today, an aqueduct draws water from the Yongding through Yuyuantan Park to the western city moat, which empties into Liangshui River south of the city. Another aqueduct draws water from Kunming Lake in the Summer Palace down through the Purple Bamboo Park and into the northern city moat, which also replenishes Shichahai, Beihai and Zhongnanhai. The northern moats are drained by the Ba River, which flows into the Wenyu River. The southern and eastern moats are drained by the Tonghui River, which also flow into the Wenyu.

This network of rivers and aqueducts are fed by reservoirs to the north of the city. The Miyun Reservoir, the largest in the municipality, is created at the confluence of the Chao and Bai Rivers, which forms the Chaobai. The Yongding, before entering the municipality in Mentougou District, is dammed to create the vast Guanting Reservoir of Hebei Province. Despite these reservoirs, the city of Beijing faces chronic water shortages due to water-intensive agriculture, industry, and population growth. Under the South-North Water Transfer Project, the city plans to draw water from the Yangtze River through the Grand Canal (China), which was built 800 years ago for transportation, but now is being upgraded into a major aqueduct.