Application of simple dredging technology in regulating pebble shoals in upper Yangtze River

The crossing shoal has straight and widened characteristics,and it is in depositing during flood season.Although the pebble and sand in crossing shoal are scoured after flood season,the water depth is not able to meet the requirements of ship′s navigation.So it is necessary to take regulation measures to increase the water depth.Qianqizi shoal is one of the typical pebble shoals of crossing sections in upper Yangtze River during dry seasons.When the shoal was regulated,the regulating structures were not arranged.Regulation measure was carried out by using only the simple dredging technology.Even so,it gets a great regulation effect.The same results were achieved in Shuishiba shoal and Heishiqi shoal in upper Yangtze River.It shows that in some crossing shoals on the upper reach of Yangtze River which the navigation obstruction degree is not high,it can get a good result by taking only simple dredging technology.