Park, J.H.; Yoo, C.I. and Yoon, H.S., 2016. Use of groundwater-table to establish a buffer zone In a barrier Island, Nakdong river estuary, South Korea. In: Vila-Concejo, A.; Bruce, E.; Kennedy, D.M., and McCarroll, R.J. (eds.), Proceedings of the 14th International Coastal Symposium (Sydney, Australia). Journal of Coastal Research, Special Issue, No. 75, pp. 113-117. Coconut Creek (Florida), ISSN 0749-0208.

A barrier island works as a buffer zone against wave and tidal forces, especially in river estuaries. To quantitatively analyze the buffer zone mechanism, understanding the wave, tide precipitation and groundwater-table by using long-term field observation is necessary. This study presents a coastal buffer zone mechanism in a barrier island (Jinudo) of the Nakdong river estuary in Busan, South Korea. For establishing a coastal buffer zone in a barrier island, we measured the groundwater at five observation points for 26 months from March 2012 and obtained wave and tidal data from a national observation station near the river mouth. We constructed a wave transformation numerical model and extracted breaking wave conditions, and then we compared data from the numerical model with a real-time groundwater data. According to the results, the buffer zone maximized up to 166.3 m from the shoreline with a wave height and period of 0.05 m and 12 sec, respectively, for 8 hours. Considering seawater infiltration, the buffer zone was observed to reduce to 125.0 m. The critical values are likely to define a coastal protection zone and vegetation distribution characteristic.