2024 Volume 80 Issue 17 Article ID: 24-17164
In 2023, 8500 m3 of sand was excavated at the north end of Ajigaura Beach and the sand was nourished at the south part of the beach for sand back pass. UAV survey was carried out on June 1 before beach nourishment and July 8 and October 10 after the nourishment to investigate beach changes. During the observation, storm waves associated with T2307 hit this area between August 10 and August 15, and nourishment material was transported away. Because UAV survey was discretely carried out, temporal changes in beach topography were not known. Therefore, time-lapse cameras were set on the beach, and photographs were taken at every 1 hour to measure wave run-up and change in foreshore. It was found that nourishment material was quickly transported away during high waves with H1/3 = 3 m and T1/3 = 10 s during T2307, and a berm with an elevation of T.P.+2.8 m was formed.
