China braces for ice flooding on Yellow River

ZHENGZHOU/LANZHOU -- China is preparing for a new round of flooding on the Yellow River, as a recent strong cold spell caused ice to build up, resulting in ice blockages, the flood prevention authority announced Tuesday.

Ice chunks appearing on a 70-kilometer segment of Yellow River in Inner Mongolia on Monday triggered the annual ice blockage response.

Preparations must be made for "the severest ice jam flood in history," according to the Yellow River flood control and drought relief office, who ordered local departments to closely monitor the situation.

The climate, which is at the end of a super el Nino and the beginning of a new la Nina, contributes to the uncertainty and complexity of this year's ice jam flood, said the National Climate Center

In readiness for potential ice jam floods, Liujiaxia reservoir, a major reservoir on the upper reaches of Yellow River, cut its water outflow from 1,208 cubic meters per second in early November to 350 cubic meters per second.

The small outflow will continue until the end of the year and be further reduced to 300 cubic meters per second in January 2017.

Ice jam floods occur in the middle and lower reaches of the Yellow River. Water builds up behind ice to form an ice dam, which blocks the river and causes flooding. It usually occurs in the springtime as the river ice begins to break up or in early winter during freeze-up.