China abounds in rivers. More than 1, 500 rivers each drain 1, 000 square kilometers or larger areas. More than 2, 700 billion cubic meters of water flow along these rivers, 5.8% of the world's total. Most of the large rivers find their source in the Qinghai-Tibet Plateau, and as a result China is rich in waterpower resources, leading the world in hydropower potential, with reserves of 680 million kilowatts.
China's rivers can be categorized as exterior and interior systems. The drainage area for the exterior rivers that empty into the oceans accounts for 64% of the country's total land area. The Yangtze, Yellow, Heilongjiang, Pearl, Liaohe, Haihe, Huaihe and Lancang rivers flow east, and empty into the Pacific Ocean. The Yarlungzangbo River in Tibet, which flows first east and then south into the Indian Ocean, boasts the Grand Yarlungzangbo Canyon, the largest canyon in the world, 504.6 kilometers long and 6, 009 meters deep. The Ertix River flows from the Xinjiang Uygur Autonomous Region to the Arctic Ocean. The drainage area for the interior rivers that flow into inland lakes or disappear into deserts or salt marshes makes up 36% of China's total land area. The Tarim River, 2, 179 kilometers long, in southern Xinjiang, is China's longest interior river.
The Yangtze River is the largest river in China, and the third longest in the world, next only to the Nile in northeast Africa and the Amazon in South America. It is 6, 300 kilometers long, and has a drainage area of 1.809 million square kilometers. The middle and lower Yangtze River's warm and humid climate, plentiful rainfall and fertile soil make the area an important agricultural region. Known as the "golden waterway", the Yangtze River is a transportation artery linking west and east.
The Yellow River is the second largest river in China, 5, 464 kilometers in length, with a drainage area of 752, 000 square kilometers. The Yellow River valley was one of the birthplaces of ancient Chinese civilization. It has lush pastureland and abundant mineral deposits.
The Heilongjiang River is north China's largest. It has a total length of 4, 350 kilometers, of which 3, 101 kilometers are within China. The Pearl River is the largest river in south China, with a total length of 2, 214 kilometers.
In addition to those endowed by nature, China has a famous man-made river -- the Grand Canal, running from Beijing in the north to Hangzhou in the south. Construction work of the Grand Canal first began as early as in the fifth century BC. The Canal flows past Beijing, Tianjin, Hebei, Shandong, Jiangsu and Zhejiang and links five major rivers -- the Haihe River, Yellow River, Huaihe River, Yangtze River and Qiantangjiang River. With a total length of 1, 794 kilometers and a drainage area of 4, 583 square meters, the Grand Canal is the longest as well as the oldest man-made waterway in the world Topography.
Alongside of abundant rivers, China also has lots of lakes. There are more than 2, 800 natural lakes, each having a surface area of over one square kilometers, and over 130 lakes, each covering more than 100 square kilometers. There are also a large number of artificial lakes (reservoirs). With different salt content, the lakes are classified as saltwater and freshwater lakes. Large lakes are mainly distributed in the middle and lower reaches of the Yangtze River and on the Qinghai-Tibet Plateau. The Boyang Lake in the south of the Yangtze River is the largest freshwater lake in China while the Qinghai Lake on the Qinghai-Tibet Plateau is the largest saltwater lake.