The impact of submarine cable laying on the surrounding marine environment in Lvhua Island

Abstract

In the process of laying the submarine cable on Lvhua Island, the sediment movement affects the surrounding area. A 2D hydrodynamic model about the Lvhua Island and its surrounding is established by MIKE 21. During the process, there are different effects in different time. The numerical simulation at the different tides is used to determine the conditions of sediment transport and to assess the impact of the project on the environment. The results show that the sediment diffuses with the tide as the concentration decreases. During the spring tide to the slack of spring tide and during the slack of spring tide to the neap tide, it mainly affects the sea area of West Lvhua Island and East Lvhua Island within half an hour after laying construction, and the suspended sediment diffuses southeast with the passage of time. During the neap tide to the slack of neap tide and during the slack of neap tide to the spring tide, it mainly affects the sea area of West Lvhua Island and Huaniao Island within half an hour after laying construction, and the suspended sediment also diffuses southeast with the passage of time. After 3 h of laying construction, the maximum range of suspended sediment for the 4 different tides is 25.54 km 2, 36.783 km 2, 24.782 km 2 and 59.322 km 2, respectively. However, the concentration of suspended sediment in the sea area is all less than 150 mg/L, having little effect on the concentration of suspended sediment in the surrounding sea.