Liao River
However, the Liao River Delta has a flat topography made up of soft sediment soil, with meandrous waterways that had a rich history of rerouting. This coupled with the risk of storm surges due to the region's low elevation, created a huge problem in flood control. This flood risk at the coastal section of the Liao River system was particularly threatening to Yingkou, a city immediately adjacent to the mouth of Daliao River and home to 2 million people. In 1958, the upriver of the Wailiao River at Liujianfang was blocked off via a river engineering project, redirecting the water flow from the Liao River "proper" entirely towards the Shuangtaizi River (which was renamed to simply the "Liao River" in 2011), effectively separating the Hun River and Taizi River from the Liao River system. Therefore, the Daliao River system is considered an independent water system of their own since 1958, and the Hun and Taizi River are no longer tributaries of the Liao River. Also, due to the Wailiao River's upstream flow being cut off, the Liao River no longer has any distributaries, therefore the Liao River Delta technically also ceased to exist from 1958 onwards, however the term remains in use to describe the area of Panjin between the Liao River's left bank and Wailiao/Daliao River's right bank.