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ABSTRACT An island resort is currently being developed within Davao Gulf and one of its important feature is a beach cove located southeast of the island. However, seasonal variations on the wave climate have caused extreme erosion within the area of interest. An investigative study on the cause of the severe erosions has thus been conducted in order to formulate mitigating measures to protect the beach. A review of the prevailing wave climate shows that this severe erosion can be attributed to southerly waves. Waves coming from this direction causes pronounced agitation of the seabed resulting in sediments smaller than 5 to 20mm to be unstable and eroded. Discussions with the developer leads to the beach engineering solution in the form of two (2) shore attached breakwaters and an offshore breakwater. The proposed solution shall protect the beach area and minimize the wave forces and allow smaller fine-sized sediments to be much stable. INTRODUCTION An island resort is currently being developed within Davao Gulf and once complete, the resort will consist of beach clubs, hotels and private villas, sports complexes and other amenities. One of the important features of the development is a beach cove fronting the Mindanao mainland along the eastern coast of the island. However, seasonal variations on the wave climate have caused extreme erosion within the area of interest and the developer's beach nourishment efforts proved to be impractical in maintaining a sandy beach profile. The developer engaged the project team to investigate the cause of the extreme sediment erosion and propose mitigating measures to protect the beach area. The paper presents the methodology undertaken in the engineering design of coastal protection structures by application of simple and straightforward concepts in coastal engineering. PROJECT AREA DATA Area Bathymetry Primary bathymetric data on the nearshore region as well as secondary bathymetric data from available nautical charts from the Philippine government's mapping authority has been consolidated ensuring that both data are referred to a common datum (mean tide level). The secondary data will help in the representation of the bathymetry on areas distant to the project site while the nearshore primary survey will help define local features of the seabed which secondary bathymetric maps do not sufficiently capture. The consolidated bathymetric map is shown in Fig. 2. The contours reveal the complex configuration of the bathymetry of the site. The slope of the coast towards the sea varies throughout the length of the coast - some are steep and some gently sloping. There are submarine headlands fronting the coast - these headlands will tend to focus wave energies to certain locations. The passage in the eastern side, between the island and the mainland, has depths of up to about −35m.