Who can introduce the flow direction of the Yellow River in the Northern Song Dynasty?

During the Northern Song Dynasty, the Yellow River burst once every 2.4 years on average. The Yellow River regulation in the middle and late Northern Song Dynasty was intertwined with the confrontation between Songliao and the imperial court at that time, which restricted the Yellow River regulation and flood control by many factors. In the eighth year of Li Qing (1048), the Yellow River branched in the Shanghu Lake in Yizhou. In the next 40 years or so, from the emperor to the ministers, there was an endless debate about whether to let the Yellow River flow northward or restore its original route. During this period, three large-scale Yellow River diversion projects were forced to resume the eastward flow of the Yellow River. However, every crossing of the East River soon ended in a big breach, which not only caused great waste, but also brought huge floods. Finally, the Yellow River still turned to the northbound route.

In the first year of Jingyou (1034), Hejian Beach Henglong (now Puyang East, Henan Province) passed through Daming, Guantao, Liaocheng and Huimin, Hebei Province, and reached Binxian County, Shandong Province. This is the first major diversion of the Yellow River in the Song Dynasty. The main stream of the Yellow River after diversion is called "Henglong Ancient Road" in history, and its route is called "Henglong Ancient Road". Henglong, therefore, the time along the river is not long. 14 years later, that is, in the eighth year of Li Qing (1048), the Yellow River burst into the lake on the city of Gezhou (now Puyang County, Hebei Province) and merged into the sea. Hang Lung's old road is completely blocked. This is the route from the northernmost part of the Yellow River to the Bohai Sea in the Song Dynasty.

The second great diversion in the Northern Song Dynasty was due to the failure of blocking the mouth, which was called "Shanghu burst the mouth" in history. In the third year of Emperor Yangdi (105 1), the Yellow River burst in Guogu, Guantao County (now Guantao County, Hebei Province), and turned south after the channel was blocked. Hebei transshipment made Li Zhongchang propose to block Shanghu Beixi, get through Liuta River and restore Henglong old road. This proposal was opposed by Ouyang Xiu. He believes that the old Henglong Road has been blocked for more than 20 years, and it is difficult to restore the abandoned channel of the Yellow River. However, the suggestion of returning to Henglong Old Road was adopted by the court. As Ouyang Xiu expected, the result of the implementation was that on the night when the Liuta River opened to divert the Yellow River water into the old Henglong Road, the water was not discharged at the fastest speed, which led to a breach. Thousands of miles north of Hebei is in Wang Yang, with numerous casualties. The reply of Henglong Old Road ended in failure.

In the fifth year of Jiayou in Song Renzong (1060), the Yellow River burst from the sixth breach in Wei County, Daming Prefecture, forming a northward flow and an eastward flow, namely the so-called "Ergu River". In the Northern Song Dynasty, people called the original Shanghu River "northward flow" and the new branch road about 60 meters wide was called "eastward flow". Among them, the east flows through Cangzhou, Laoling and Wudi into the sea.

After the Yellow River divides into north and east flows, the new channel has been unstable and the old channel has shrunk, so the old and new channels still often overflow. At that time, there were two main ideas for flood control and regulation of the Yellow River in the Northern Song Dynasty: the first idea was to maintain the northward flow of the Yellow River and slow down the flood in Hebei by building dikes; The second proposition is to block the old channel of the north stream and stabilize the new channel of the east stream. Song Shenzong and Prime Minister Wang Anshi preferred the latter, but in view of the lessons of Liuta River, they sent people to build a dam at the mouth of Ergun River to stop the river from flowing eastward. Sima guang first agreed to the proposal of returning to the river. After on-the-spot investigation, he thinks that the shallow and narrow eastward flow and incomplete dikes will definitely lead to overflow, so the matter of retreating from the river should be delayed. However, anxious to return's Song Shenzong and Wang Anshi blocked the Beiliu River in August of the second year of Xining (1069) when the eastward flow was smooth and the Beiliu River was shallow. As a result, the Yellow River burst east of Xujiagang and south of Jingkou, and several counties located between Beiliu and Donglu suffered heavy disasters.

After Beiliu was closed, the court took many measures to maintain Dongxi, but Dongxi was still broken. In the fourth year of Yuanfeng (108 1 year), the Yellow River burst in Xiaowu, Ganzhou, and flowed into the Royal River in the north. Generally, it entered the Yongji Canal along the old road of Wangmang River and passed through several counties before entering the sea. Since then, the east flow has been cut off, and the Yellow River has resumed its north flow. After Zhezong ascended the throne, in order to achieve the goal of "defending Liao" with the danger of the Yellow River, the discussion of returning to Hedong resumed. At that time, Wang, the representative of the Uighur school, specifically listed the seven hazards of the northward flow of the Yellow River, while another representative advocated that "setting risks" should precede "harnessing the river". The opposition Su Zhe, Zeng Zhao and others fought back. Both sides have held their own opinions for several years. However, the idea of returning to the Donghe River is very consistent with the intention of the rulers of the Liao Dynasty in the Northern Song Dynasty. Yuan You eight years in May (1093), the court returned to the river. As a result, a more serious flood occurred than in the second year of Xining (1069). Six years later, the Yellow River broke its inner mouth, and the eastward flow was cut off, and the main stream of the Yellow River resumed its northward flow route.