Abstract

Based on the latest flow regime, the equivalent water levels at Jiahetan Hydrologic Station had been lowered 0.4 – 0.6 meters, comparing with that in the end of flood season last year, during the water and sediment regulating operation period in 2006 due to the natural cutoff of misshapen river bend in Changdi – Jiahetan river reach before and after the date on May 1, 2006. It is analyzed that the impact of river bend cutoff on improving flood carrying capacity in local river reaches is significant; it should be paid enough attention to adverse effect of excess bending flow path planned for river regulation on channel flood carrying capacity; and a suggestion is put forward to fundamentally eliminate disadvantage river regime happened again.

Keywords: River regime (cutoff), flood carrying capacity, Darcy-Weisbach formula, lower Yellow River