We surveyed the flood in the Second Songhua River, Lalin River, the East Liao River and the middle and downstream of the Liao River, calculated the peak discharge in three of these reaches and confirmed the ranking and recurrence interval of this flood.
From the investigation of the flood, we know that the rainstorm and floods which are concentrated in the second Songhua River, Lalin River, the East Liao River and the middle and downstream of the Liao River. The flood in 1856 was similar to the flood in 1953 in the second Songhua River above the Fengman reservoir, not only in the flood discharge but also the distribution in the region. The flood on 20th August, 1953 was caused by the cyclonic rain in Bohai Sea, which was influenced by the typhoon, and the peak discharge was 15200 cubic meters per second after the reduction. The flood mainly came from Huifa River, Hongshizi River and area between Wudaogou and Fengman.
The peak discharge was 15300 cubic meter per second in 1856 in Fengman. Because the development of the Fengman area was late and there was still bushland in 1856, the reaches on the upper stream didn’t have the record of this flood. But there is some information about Qing River and the East Liao River shows that there were a lot of floods in 1856. Apart from this, an old person in Qing River, Taiwanling said that the flood in the sixth year of Xianfeng destroyed the Chaoyang town in the east of Hailong city. So to sum them up, there also are a lot of floods in Huifa River in 1856 and the main water came from Fengman. Besides, the flood in 1856 was the flood which had the most discharge in the branches under Fengman such as Aolong River, Tuanshanzi River and Yinma River. According to the flood information, the flood in the Second Songhua River mainly came from branches above Fengman.
The flood was also a large flood in Lalin River in this year. We have investigated that there were flood in the Longfengshan reservoir, Liangjiashan reservoir and Huitang Ditch but the upper stream of Lalin River and there are some reasons, such as the late development and few inhabitants around. So, we think the flood was a very large flood in Lalin River.
The flood in 1856 in the reach of Tieling in Liao River was mainly come from Liao River, Qing River, Chai River and Fan River.
Although we don't have some quantitative data for the flood disaster, there are a lot of qualitative description in historical documents and investigated information such as the General Annals of Jilin and the County Annals of Kaiyuan. When we investigated in Ao River, some people told us that the crops were been flooded in 6th year, Xianfeng. Some people told us that there was a large flood forced the local people to get on trees to avoid it in Yinma. And also some people in Kaiyuan, Qing River told us some villages were washed away by the flood. This information demonstrated the large areas where were influenced by this flood.
The information is provided by Disaster Risk Reduction Knowledge Service.