The Yangtze River, in central China, is the longest river in Asia and the third-longest in the world. Rising in western Qinghai (Tsinghai) province, it flows 5,990 km (3,720 mi) to the East China Sea. Its drainage basin covers more than 1,827,000 km2 (705,400 mi2). The river's mouth discharges 22,000 m3 (776,923 ft3) per second.
ncient texts call the Yangtze the "Great River," and it is commonly referred to in China as Chang Jiang (Ch'ang Chiang, or "Long River"). The name Yangtze, although applied to the whole river in the West, is only a local name for the river in Jiangsu (Kiangsu) province.
The Yangtze River System Facts
The Yangtze and its tributaries are navigable for a total length of 30,000 km (18,640 mi); the river itself is ice-free all year. The volume of transportation on the Yangtze River system is greater than the total traffic on all the other waterways and rivers of China combined.
Oceangoing vessels can sail inland as far as Wuhan (Wu-han). Yichang (I-ch'ang), often considered the head of navigation of the river, is accessible to 8,000-ton vessels during the summer. Five of China's largest cities are on or near the river system; they are Shanghai, Wuhan, Chongqing (Chungking), Chengdu (Ch'eng-tu), and Nanjing (Nanking).
Flooding along the Yangtze caused several hundred thousand deaths in the 20th century alone. The river has a hydroelectric potential of 220,000,000 kW. Several multipurpose projects have been built since 1949. They include the Jingjiang (Kingkiang) flood retention reservoir north of Tongting (Tung-t'ing) Lake and the Gezhouba (Kechoupa) Dam near Yichang.
Construction of the Three Gorges Dam near Chongqing, designed to control flooding and provide some 10% of China's electricity, was approved in 1992; the river was diverted from its natural course between 1997 and 2006 so the dam could be built.
The controversial project submerged the scenic Yangtze gorges and created a huge lake displacing 1.3 million people. By 2012, it was estimated that landslides and bank collapses in the area might displace another 100,000 people.
Precipitation in the river basin averages 1,000 mm (40 in) a year. Because the river basin is vast, temperatures vary greatly. They range from below −15° C (5° F) in the west to 5° C (41° F) in the east in winter and from 10° C (50° F) in the west to 30° C (86° F) in the east in summer.
The Yangtze rises on the Tibetan Plateau in western Qinghai at an elevation of more than 5,400 m (17,700 ft). Eight major tributaries join it as it flows eastward to the East China Sea. They are the Yalong (Ya-lung), Min, Jialing (Chia-ling), Han Shui, Wu, Yuan, Xiang (Hsiang), and Gan (Kan). Upstream from the city of Yibin (I-pin) in Sichuan (Szechwan) province, the river's upper course has a V-shaped cross profile and a gradient of 2 m per km (6.6 ft per mi).
The river's middle course extends from Yibin to Yichang; it contains the three famous Yangtze gorges. Before the construction of the Three Gorges Dam, the depth of the river in the gorges was 152 to 183 m (500 to 600 ft), making it the world's deepest river.
From Yichang to the sea, the river's lower course has a gradient of 25.6 mm per km (1 in per mi). The delta below the city of Zhenjiang (Chen-chiang) is less than 10 m (33 ft) above sea level. The river carries an average 142 million metric tons (156.5 million U.S. tons) of sediments annually into the sea.
Approximately 70% of China's rice comes from the Yangtze Basin. Liangzhu City, a notable example of early urban civilization based on rice cultivation, is located in the Yangtze basin. The Archaeological Ruins of Liangzhu City date back to the late Neolithic period.
They were declared a UNESCO World Heritage Site in 2019. The property includes urban planning, earthen monuments, a system of water conservation, and cemeteries that reflect an urban hierarchy. Where the land is not cultivated, the area is covered by mixed forest.
In 2001 the Chinese government and the United Nations Environment Programme announced an ambitious plan to prevent massive flooding in the river basin; in 1998 such flooding killed more than 3,000 people and forced the relocation of another 14 million.
The floods were deemed to have been caused by deforestation and overgrazing, erosion, and the loss of rivers and wetlands. The project would reduce erosion by reclaiming forests and grasslands along the upper and middle courses of the river, which had been cleared for farmland; thousands of lakes and natural drainage systems were to be restored.
The controversial multibillion-dollar South-to-North Water Transfer Project will divert water northward from the Yangtze to the Huang He (Hwang Ho, or Yellow River) and the Huai and Hai rivers, all of which are suffering the effects of overpumping and pollution. It will especially aid drought-prone northern cities such as Beijing (Peking) and Tianjin (Tientsin).
The first phase of the South-to-North project -involving broadening and deepening the existing Grand Canal to divert water from the Yangtze River basin toward the port of Tianjin- was completed in 2013. The second phase -a canal diverting water from the Danjiangkou dam in Hubei to Beijing- was completed in 2014. Nevertheless, the gap between water supply and demand remained significant and continued to increase.
Scientists warned that dam building on the Yangtze, fueled in part by China's growing need for electricity, could have serious environmental consequences. By the early 21st century, 46 large dams were planned or under construction on the river.
A 2007 study indicated that about 10% of the Yangtze had become irreversibly polluted. In addition to fertilizer and pesticide runoff, it is estimated that at least 12.7 billion metric tons (14 billion U.S. tons) of waste are discharged into the river each year.