Several submarine canyons develop offshore of the Aramata region of the Shimoni-ikawa coast in Toyama Bay. The Kurobe River flows into the sea immediately east of this area, and a large amount of sediment has been supplied to this area as a source of westward longshore sand transport. However, after the construction of the detached breakwaters, offshore sand transport was accelerated and beach erosion occurred downcoast. In this study, aerial photographs and bathymetric survey data were analyzed and then, the mechanism of this offshore sand transport was investigated using the BG model proposed by Serizawa et al. (2006).
