Daliao River

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The Daliao River (simplified Chinese: 大辽河; traditional Chinese: 大遼河; pinyin: Dàliáohé, "Great Liao River") is a major river system in eastern Liaoning province of Northeast China, and formerly the main distributary of the lower Liao River until 1958. The Daliao River proper is formed from the confluence of three rivers at the border between Anshan's Haicheng city and Panjin's Panshan County, after where it runs a length of 94 kilometres (58 mi) covering a catchment area of 1,926 square kilometres (744 sq mi), before coursing meandrously southwest and draining into the Liaodong Bay just west of Yingkou.

The principal river of southern Northeast China, the Liao River, historically bifurcates into two distributaries near the Liujianfang Hydrological Station (六间房水文站) at Xinkaihe Town (新开河镇) of Anshan's Tai'an County, forming the Liao River Delta. The eastern distributary, called the Wailiao River, was originally the larger one and the main body of lower Liao River. It travelled southwards to pick up two large tributaries the Hun River and Taizi River, at a confluence locally referred as the "Trident River" (三岔河). After the three rivers merged, the resultant large river then adopted the new name as Daliao River.

However, the low elevation and the flat, waterway-rich (and often rerouting) topography of the Liao River Delta region created a huge problem in flood control. During monsoon seasons the storm surges from the Bohai Sea could go as far inland as the Trident confluence, and when meeting the voluminous upstream water from the Liao River, would frequently exceed the capacity of river channels causing massive spill-over flash floods. This flood risk particularly threatened the cities of Yingkou (which is immediately adjacent to the Daliao River mouth and home to 2 million people) and Haicheng (which has over 1 million residents). In 1958, a river engineering project was conducted, and the upriver of the Wailiao River at the Liao River bifurcation was blocked off, redirecting the Liao River flow entirely towards the Shuangtaizi River (双台子河), the originally smaller western distributary of the river delta. This separated the Wailiao, Hun and Taizi Rivers from Liao River permanently, making the Daliao River an independent river system since 1958.