The Huai River (), formerly romanized as the Hwai, is a major river in China. It is located about midway between the

Yellow River The Yellow River or Huang He (Chinese: , Mandarin: ''Huáng hé'' ) is the second-longest river in China, after the Yangtze River, and the sixth-longest river system in the world at the estimated length of . Originating in the Bayan Ha ...

and

Yangtze The Yangtze or Yangzi ( or ; ) is the longest river in Asia, the third-longest in the world, and the longest in the world to flow entirely within one country. It rises at Jari Hill in the Tanggula Mountains (Tibetan Plateau) and flows ...

, the two longest rivers and largest drainage basins in China, and like them runs from west to east. Historically draining directly into the

Yellow Sea The Yellow Sea is a marginal sea of the Western Pacific Ocean located between mainland China and the Korean Peninsula, and can be considered the northwestern part of the East China Sea. It is one of four seas named after common colour ter ...

, floods have changed the course of the river such that it now primarily discharges into the Yangtze. The Huai is notoriously vulnerable to flooding. The

Qinling–Huaihe Line The Qinling–Huaihe Line () is a reference line used by geographers to distinguish between northern and southern China, corresponding roughly to the 33rd parallel. Qinling refers to the Qin Mountains, and Huaihe refers to the Huai River. Runn ...

, formed by the Huai River and the

Qin Mountains The Qinling () or Qin Mountains, formerly known as the Nanshan ("Southern Mountains"), are a major east–west mountain range in southern Shaanxi Province, China. The mountains mark the divide between the drainage basins of the Yangtze and Yellow ...

, is sometimes regarded as the geographical dividing line between Northern and southern China. This line approximates the January isotherm and the

isohyet A contour line (also isoline, isopleth, or isarithm) of a function of two variables is a curve along which the function has a constant value, so that the curve joins points of equal value. It is a plane section of the three-dimensional grap ...

in China. The Huai River is long with a drainage area of .

Course

The Huai River originates in Tongbai Mountain in

Henan province Henan (; or ; ; alternatively Honan) is a landlocked province of China, in the central part of the country. Henan is often referred to as Zhongyuan or Zhongzhou (), which literally means "central plain" or "midland", although the name is al ...

. It flows through southern Henan, northern

Anhui Anhui , (; formerly romanized as Anhwei) is a landlocked province of the People's Republic of China, part of the East China region. Its provincial capital and largest city is Hefei. The province is located across the basins of the Yangtze River ...

, and northern

Jiangsu Jiangsu (; ; pinyin: Jiāngsū, alternatively romanized as Kiangsu or Chiangsu) is an eastern coastal province of the People's Republic of China. It is one of the leading provinces in finance, education, technology, and tourism, with its ca ...

where it pools into

Lake Hongze Hongze Lake or Lake Hungtse () is the fourth largest freshwater lake in China, in Jiangsu Province, China and is encompassed by the prefecture-level cities Suqian (Sihong County and Siyang County) and Huai'an (Xuyi County and Hongze County). La ...

. Nowadays the Huai River then runs southwards as the Sanhe River by way of the

Gaoyou Lake Gaoyou Lake () is the sixth largest freshwater lake in China, it is located between Anhui Province and Jiangsu Province. In a sense Gaoyou Lake is a manmade lake, and its creation is part of a long story about flood control and hydraulic engineerin ...

and

Shaobo Lake Shaobo Lake () is a freshwater lake in Jiangsu Province, China, it is located between Gaoyou and Yangzhou. Shaobo Lake is a part of the Huai River system as the Huai River flows south through Shaobo Lake on its way to the Yangtze River like Gaoyo ...

emptying into Yangtze River at Sanjiangying (三江营) near

Yangzhou Yangzhou, postal romanization Yangchow, is a prefecture-level city in central Jiangsu Province (Suzhong), East China. Sitting on the north bank of the Yangtze, it borders the provincial capital Nanjing to the southwest, Huai'an to the north ...

. There is also a passage called the Huaihe Sea Entryway and Subei Irrigation Canal that passes

Huai'an Huai'an (), formerly called Huaiyin () until 2001, is a prefecture-level city in the central part of Jiangsu province in East China, Eastern China. Huai'an is situated almost directly south of Lianyungang, southeast of Suqian, northwest of Yan ...

empties into the sea at Biandan Port. A separate course runs north by way of the Huaimu River and Huai Shu River and connects the Huai River system with the Xinyi River (part of the Yishusi River system) which exits into the sea at Guanyun in

Lianyungang Lianyungang () is a prefecture-level city in northeastern Jiangsu province, China. It borders Yancheng to its southeast, Huai'an and Suqian to its south, Xuzhou to its southwest, and the province of Shandong to its north. Its name derives f ...

. In part to circumvent flooding, in

province the Huai river system is interconnected with different waterways and thereby forms part of the Grand Canal.

History

Historically, the Huai River entered the

at Yunti Pass (modern day Yunti Village, in Huangwei Town of

Xiangshui County Xiangshui County () is a coastal county under the administration of Yancheng, Jiangsu province, China. The northernmost county-level division of Yancheng, it borders the prefecture-level cities of Lianyungang to the northwest and Huai'an to the s ...

) through a broad and level lower course. It was long used to irrigate the surrounding farmlands, and was the center of an extensive network of canals and tributaries. Beginning in 1194, however, the

to the north repeatedly changed its course southwards to run into the Huai River. The resulting silting was so heavy that after the Yellow River changed back to its northerly course for the most recent time in 1897, the geography of the Huai River basin was changed significantly by the creation of new high lands, lakes, and the built-up silt of the Yellow River's historical southern course. As a result, water from the midsection of the river could not easily flow into the lower section, while water in the lower section could not find an outlet to the sea. The problem worsened in the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...

, when the

Nationalist Nationalism is an idea and movement that holds that the nation should be congruent with the state. As a movement, nationalism tends to promote the interests of a particular nation (as in a group of people), Smith, Anthony. ''Nationalism: Th ...

government, in an attempt to check the pace of the Japanese invasion, flooded the lower Huai basin by opening the Yellow River's southern levee. The main stem of the Yellow River flowed through the levee breach for the next nine years, further disrupting the Huai river system. The result of these changes was that water from the Huai River pooled up into

, and then ran southwards towards the Yangtze River. Major and minor floods occurred frequently, with the area suffering droughts in between floods. In the 450 years to 1950, the Huai River saw, on average, 94 major floods per century. Attempts to solve the Huai River's problems have focused on building outlets for the Huai River into the Yangtze River and the sea. Currently, the major part of the river's flow enters the Yangtze River via Lake Hongze. The

North Jiangsu Main Irrigation Canal The North Jiangsu Main Irrigation Canal () (often called the Subei Canal) is located in the lower reaches of the Huai River, one of the major rivers in the north of Jiangsu Province, China. It originates at Gaoliangjian on Hongze Lake and runs thr ...

also diverts some of its water along its old historical course to the sea, and is planned to be upgraded with a new parallel channel. Several former tributaries also carry some water to the sea.

Tributaries

There are many tributaries of the Huai River. There are 15 main tributaries cover an area of more than each, and 21 main tributaries have a catchment area larger than . / The main tributaries on the Huai river (listed from upstream to downstream) are as follows:

References

External links

Huai River
{{Authority control Rivers of Jiangsu Rivers of Henan Rivers of Anhui Tributaries of the Yangtze River