Photo taken on July 3, 2018 shows water gushing out from the Xiaolangdi Reservoir on the Yellow River in central China's Henan Province. The reservoir started to discharge water at 2,300 cubic meters per second Tuesday. (Xinhua/Miao Qiunao)

Tourists watch water gushing out from the Xiaolangdi Reservoir on the Yellow River in central China's Henan Province, July 3, 2018. The reservoir started to discharge water at 2,300 cubic meters per second Tuesday. (Xinhua/Miao Qiunao)

Tourists watch water gushing out from the Xiaolangdi Reservoir on the Yellow River in central China's Henan Province, July 3, 2018. The reservoir started to discharge water at 2,300 cubic meters per second Tuesday. (Xinhua/Miao Qiunao)

Tourists watch water gushing out from the Xiaolangdi Reservoir on the Yellow River in central China's Henan Province, July 3, 2018. The reservoir started to discharge water at 2,300 cubic meters per second Tuesday. (Xinhua/Miao Qiunao)