Aerial photo taken on July 21, 2020 shows the Liujiaxia reservoir in Linxia Hui Autonomous Prefecture, northwest China's Gansu Province. The water flow in the upper stream of the Yellow River has been increasing due to rainfall. The Lanzhou hydrological station saw the second flood of the river this year with the water flow of 3,000 cubic meters per second, which occured at 8:42 p.m. on Monday. Authorities raised the emergency response for flood control to Level IV, as the water flow of the river surged to 3,320 cubic meters per second at 8 a.m. on Tuesday and the floodwater rose above alert level. Since strong rain will continue to lash parts of northwestern China from Tuesday to Thursday, reservoirs in the upper stream of the Yellow River have raised their discharge volume to battle the flood. (Xinhua/Chen Bin)