General Introduction of the
Yangtze River

What is the total length of Yangtze River, and its drainage area?
Yangtze River is the longest river in the People's Republic of China, and is one of the longest in the world. The total length of Yangtze River is over 6300 km. It ranks the third in the world, only shorter than the Nile and Amazon.
The section above Yichang is the upper reaches with a length of 4504 km and drainage area of 1 million km2; the one from Yichang to Hukou (connection of Poyang Lake to the River) is the middle reaches with a length of 955 km and drainage area of 680,000 km2; and below Hukou is the lower reaches with a length of 938 km and drainage area of 120,000 km2. The total drainage area of Yangtze River is 1.8 million km2 covering 18 provinces and cities.

How much is the water resource of Yangtze River?
Yangtze River has very rich water resources. The average annual precipitation is 1100 mm, and the total amount of water is 975.5 billion m3, 36% of the total amount in China.
Yangtze River also has rich water power resources. According to surveys of its mainstream and branches, the theoretical reserves is 268 million kw, 40% of the national reserves, among which 197 million kw can be developed. The average production of power generation is 100 million kwh, 53.4% of the total in China. The water power of Yangtze River equals to that of 560 million tons of coal annually, about 1.46 times of that in America.

How is the navigation in Yangtze River?
Yangtze River is the one with the most developed inland navigation. The mainstream has always been called "Gold Waterway".
There are altogether 3600 rivers open for navigation in the mainstream and branches of Yangtze River with a mileage of 70,000 km, 65% of the total inland mileage of China. In the late 80's, the volume of goods transported was 80% of the total in China. The 2921-km mainstream below Xinshi County is open for navigation all around the year. Ships over 1500 tons can go upstream 2429 km to Chongqing, ships over 3000 tons 1353 km to Linxiang, ships over 5000 tons 1143 km to Wuhan, and ships over 20,000 tons 437 km to Nanjing.

What is the social and economic situation of Yangtze River valley?
The land area of Yangtze River valley is 19% of the total land in China, among which there are 336 million mu ( equal to 55.5 million acre ) of arable land, 716 million mu ( 118 million acre ) of forest land, 469 million mu ( 77.4 million acre ) of pastureland, 113 million mu (18.6 million acre ) of water area, 297 million mu ( 49 million acre ) of uncultivated land and 745 million mu ( 122.9 million acre ) of other land.
According to statistics in 1983, the total population of Yangtze River valley is 358 million, nearly 35% of the national population. The population density of the valley is 199 per km2, 1.86 times of the national average. The density of the upper reaches area is 135 per km2, the middle reaches area 241 per km2, and 352 per km2 for the lower reaches.
Like the Yellow River, Yangtze River is also called the cradle of Chinese nationality. Because of the favourable natural conditions and long history of development, Yangtze River valley has been an important area of agricultural production since early time. Sichuan in the upper reaches was called "Nature's Storehouse". Hunan and Hubei in the middle reaches was named the nation's granary. The delta in the lower reaches has the reputation of "a land of fish and rice". Industry in the valley, especially in the middle and lower reaches, is also developed. Chongqing, Wuhan and Shanghai are three major economic centres in the valley. The gross output value of industry and agriculture in the valley is 40% of the national value.

What is the history of flood disasters in Yangtze River valley?
A lot of areas suffered flood in Yangtze River valley. In mountain areas of the upper reaches and branches, there are such disasters as landslide, landslip and mud-rock flow caused by flood and rainstorm. In plains of middle and lower reaches, flood often occurs overflowing riverbed. The middle and lower reaches area is the one that suffers most. According to historical record, there are 214 floods from Han Dynasty, 185 B.C., to late Qing Dynasty, 1911, about once every 10 years. In 1788, the peak flow of Yichang reached 86,000 m3/sec. Jingjiang dyke was broken at 22 places. Jingzhou City was flooded, much land was inundated, and a lot of people died. In mid-19th century, two extremely huge floods occured in 1860 and 1870. The flood broke the dyke at south bank of Jingjiang, and inundated an area of over 30,000 km2. In 1930s, the flood in 1931 inundated a land area of 50.9 million mu (8.4 million acre) and caused the death of 145,000 people. Hankou City was flooded over 3 months. The flood in 1935 inundated a land area of 22.64 million mu (3.74 million acre) and caused the death of 142,000 people. There was flood in 1949, too, and a great loss was caused. After the founding of the People's Republic of China, the Party and the government paid great attention to water control construction. Dykes and dams were repaired and strengthened. In 1952, Jingjiang Flood-diversion Project started. In 1954, the greatest flood of this century occured. The government took a series of flood-diversion measures and saved major dykes and cities. However, the loss was still great. 47.55 million mu (7.8 million acre) of cultivated land was inundated, the disaster population was 18.88 million and over 30,000 people died. The Jingguang Railroad was closed for 100 days. Huge economic loss caused impact to the national economy.

How many projects have been built since the liberation and what are their roles?
After the establishment of New China, the people's government started to harness and develop Yangtze River. Especially, after the 1954 flood, the Party Central decided to make overall planning of Yangtze River valley. In 1959, Yangtze River Valley Planning Office (YRVPO) formally submitted the report of comprehensive use and development of Yangtze River valley. Great achievements have been made for the past thirty years with the effort of related organizations and all the people in Yangtze River valley.
Flood prevention: We have repaired and strengthened the 3570-km dykes and dams along the middle and lower reaches. 4.05 billion of stone and earth are completed. We also straightened the Jingjiang section to raise its ability of floodwater releasing. Furthermore, we built Jiangjiang flood diversion project, Dujiatai flood diversion project in middle-and-lower-reaches plains and made some other flood storage areas. The capacity of flood storage reached 50 billion m3.
Comprehensive Use: We built 105 large reservoirs and a lot of medium-sized and small reservoirs. These reservoirs played some roles in flood prevention of Yangtze River. However, the standard of flood control ability is still very low. Currently the releasing quantities of the middle and lower reaches of Yangtze River are: Jingjiang section 60000-68000m3/sec; Chenglingji 60000m3/sec; Wuhan 70000m3/sec; Hukou 75000-80000m3/sec. Floods of once in 10-20 years can be prevented only by dykes and dams. For floods over this standard, we should use flood diversion and storage areas. For such floods as the one in 1954, the diversion and storage quantity can reach 50 billion m3 to protect major areas.
Irrigation: We have built over 48,000 reservoirs with a total capacity of 122.2 billion m3 since the founding of new China. By the end of late 80s, the irrigation area reached 227 million mu.
Power generation: We have built and put into operation hydro power stations of 11.52 million kw. 5.63 million kw of power stations are under construction. The total capacity of small power stations was over 3 million kw. The general level of development is relatively low, and it is only 10% of the water power resources that can be developed.
Navigation: Chuanjiang water course has been improved since 1949. Rapids has been erased. The measure of the water course has been raised from 33(2.1(100m (width(depth(winding radius) to 60(2.9(750m. The navigation period from Chongqing to Yichang is shortened from 10 days to 6 days. 335 shiplocks have been built on the mainstream and branches.
After all, great achievements have been made in the development of Yangtze River valley since new China was established. However, as the middle and lower reaches area is densely-populated and economically-developed, we should pay much more attention to flood prevention in this area.