How long does the Songhua River last?

The opening time of Songhua River is different every year, but it is usually in April every year.

Nenjiang River, a tributary of Songhua River, flows from north to south, and the middle and lower reaches open 3 ~ 5 days earlier than the upper reaches, rarely forming ice dams. The main stream of Songhua River flows from south to north along the northern slope of Changbai Mountain. Since Fengman Hydropower Station was put into operation at 1942, the 70 ~ 100 km downstream reach is no longer frozen even in severe winter, and the ice sheet in the downstream reach is obviously thinner, so the ice flood is extremely mild.

From the confluence of Sancha River to the northeast, the river below Harbin enters the low mountain area, and there are platforms and low mountains on both sides. The river near Yilan is obviously narrowed, with the narrowest point of only about 300m, and it passes through Sansheng Shoal, with a length of 27km. The rivers below Yilan are multi-curved and multi-branched, and the downstream position is north, and the ice layer is thick, so the river starts later than the upstream, and it is easy to form an ice dam when it starts, and the ice damage is more serious.

Extended data:

After the flood season of 1998, the precipitation in Nenjiang River basin in the upper reaches of Songhua River was obviously too high, and three consecutive floods occurred. The first flood occurred from the end of June to the beginning of July, the second flood occurred from the end of July to the beginning of August, and the third flood occurred in mid-August, which was a major flood in Nenjiang River Basin.

Affected by the inflow of water from various tributaries, the water level in the main stream of Nenjiang River rose rapidly, and the highest water levels at Tuanjie, Qiqihar, Jiangqiao and Dalai hydrological stations exceeded the historical measured highest water levels by 0.25, 0.69, 1.6 1 and 1.27 meters respectively. Under the condition of execution of the 6 th outlet of Nenjiang levee, the flood peak discharge of Qiqihar, Jiangqiao and Dalai stations all exceeded 1932.