BEACH CHANGES ALONG EAST SHORE IN LINGAYEN BAY SUBJECT TO HIGH-ANGLE WAVES

Abstract

 Lingayen Bay of a slender shape located 150 km north of Manila faces the South China Sea, and it satisfies the condition of High-angle waves because of its slender shape, causing the predominance of longshore sand transport. Villages are located along the coastline, and groins have been constructed along the shoreline to protect these villages against erosion. However, the spatial imbalance of longshore sand transport was triggered by the construction of these groins, resulting in erosion downcoast of each groin. In this study, the shoreline changes in the vicinity of the groins were investigated using satellite images as well as field observation on February 23, 2018, taking a concave shoreline between the Balili and Aringay Rivers in Lingayen Bay as an example. On the basis of these data, future measures were discussed.