Flood Routing Characteristics and Flood Control Situation in the Lower Yellow River since Xiaolangdi Reservoir Operation

At present, with the operation of Xiaolangdi Reservoir, the river cross - section form in Lower Yellow River is adjusted and some new flood routing characteristics appears. Based on the analysis of the erosion and deposition variation and cross-sections form, cooperating with research of recent physical model flood experiment, the new flood characteristics adjustment is discussed in this paper. It is considered that the channel flow capacity has increased for erosion since the first Water and Sediment Regulation while the capacity of Gaocun - Sunkou - Aishan channel increases less than other reaches. So the flood crest cutting decreases in the meandering channel while it increases relatively in Gaocun - Sunkou - Aishan channel, the flood routing duration is shortened, while the proportion of routing duration in Gaocun - Sunkou - Aishan channel occupying whole duration is more than other channel. The water level at the same discharge falls wholly while it falls at Gaocun and Sunkou less than other stations. Therefore, when the flood routes to the lower channel fast, at the same time, the flood crest cutting is less than ever, the water volume routing to the down flow increases obviously. When flood arrive the channel below Gaocun, the disaster situation would be aggravated.