Preliminary study on the distribution of artificial reefs by using multibeam echo sounder

In order to investigate the distribution of artificial reefs (AR) in a coastal area for nautical charting and the stability study of the cast AR, a multibeam echo sounder (MBES) was used. Side scan information can only be favorably used for the qualitative understanding of the distribution of AR. Deployment of a side scan towfish in a coastal area is a little difficult. The condition of settlement and scouring of AR is very hard to inspect by divers or ROV due to water turbidity. Therefore, it is a good idea to investigate the distribution, subsidence, horizontal movement, sand transport, and scouring of AR by using MBES. Bathymetry together with local current data around AR can be the basis of studying the mechanism of scouring and subsidence. High density and narrow beamwidth bathymetric data provided by MBES are used to delimit the distribution of AR. MBES data together with a side scan image can help to interpret the orientation of the AR