The Huai River,<!--Chinese in infobox; see WP:MOS-ZH--> formerly romanized as the Hwai, is a major river in East China, about long with a drainage area of . the two longest rivers and largest drainage basins in China. Historically draining eastwards directly into the Yellow Sea, erosion from floods have changed the course of the river such that it now primarily discharges into the Yangtze. The Huai River is, to this day, notoriously vulnerable to flooding.

The Qinling–Huaihe Line, formed by the Huai River and the Qin Mountains, is sometimes regarded as the geographical dividing line between northern and southern China. This line approximates the January isotherm and the isohyet in China.

Course

The Huai River originates in Tongbai Mountain in Henan province. It flows through southern Henan, northern Anhui, and northern Jiangsu where it pools into Lake Hongze.

Nowadays the Huai River then runs southwards as the Sanhe River by way of the Gaoyou Lake and Shaobo Lake, emptying into the Yangtze River at Sanjiangying (三江营) near Yangzhou.

Beginning in 1194, however, the Yellow River 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 Sino-Japanese War, when the Nationalist 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 main tributaries on the Huai River (listed from upstream to downstream) are as follows:

{| class="wikitable"

|+

|-

! North bank !! South bank

|-

| Hong River (洪河) || You River (游河)

|-

| Ying River (潁河) || Shi River (浉河 [河流])

|-

| Xi Fei River (西淝河)|| Zhu Gan River (竹竿河)

|-

| Guo River (涡河)|| Zhai River (寨河)

|-

| Xin Bian River (新汴河)|| Huang River (潢河)

|-

| Kui Sui River (奎濉河)|| Bai Lu River (白露河)

|-

| || Shiguan River (史灌河)

|-

| || Pi He River (…)

|-

| || Dong Fei River (东淝河)

|-

| || Chi River (池河 [淮河])

|}

References

  • Huai River