Monitoring of Coastal Geomorphological Changes in Wolchun Beach after LNG Base Construction

Abstract

Kim, I.H.; Kim, J.H.; Nam, J.M.; Lee, H.S., and Song, D.S., 2019. Monitoring of coastal geomorphological changes in Wolchun Beach after LNG base construction. In: Lee, J.L.; Yoon, J.-S.; Cho, W.C.; Muin, M., and Lee, J. (eds.), The 3rd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 91, pp. 366-370. Coconut Creek (Florida), ISSN 0749-0208.Constructions of industrial facilities nearby coastal region often break a natural equilibrium between sediment budget and littoral current condition. The Wolchun beach, which is facing East Sea of South Korea, had a longshore stretch of 1.9 km before the LNG storing base was constructed. In this study, we analyzed the change patterns of the Wolchun beach topography caused by the installation of artificial structures, as well as coastal geomorphological changes. The control points in the study area were divided into 8 sections, each spaced 50 m pitch apart, for the trend analysis of the beach profiles. Also, the sea zone with 1.35 km2 area was divided into 6 sections with 300 m × 750 m per section, for the monitoring of water depth variation. The surveying results show that the area of the northern side of the Wolchun beach near the LNG storage base was continuously increased due to the accumulation of sediment after the construction of LNG base. On the contrary, the continuous erosion occurred on the south side of Wolchun beach, and it was observed that the water depth near the surf zone is deepened. Also, the bathymetric change of the test area was occurred actively, and the significantly unstable change of water depth in the region of about -10 m ∼ -15 m was confirmed to be generated by the breakwater with the disrupting of operable wave condition. It is found that the natural equilibrium has been collapsed along the unexpectedly formed shielding zone after the construction of the LNG base and the breakwater on the outside of the base.