Study on the Sediment Transport and Nearshore Evolution Situation in the Sea Area Southwest of Yangma Island

A general siltation occurred in the sea area southwest of Yangma Island in the past 30 years, and the mean bottom accretion rate in the area was 1.5 cm/a with an accretion rate up to 10 cm/a in some area. The progradation rate of coastline east of the Yuniao River was about 1 to 6 m/a. The surficial sediment in the sea area has a trend to become finer, and the quick siltation in the sea area is related to the energy dissipation due to the island shield and the seawall blocking. The bottom accretion has obvious effect on the design plan of water intake. In this paper, the hydrodynamics, sediment transport and nearshore evolution situation in the sea area are analyzed, and the design plans of water intake are also discussed.