A numerical simulation of the beach changes on the Seisho coast was carried out using a contour-line-change model considering changes in the grain size. The applicability of the simulation model to a gravel-sand beach with protruding rocks was verified by comparing the calculated and observed changes after storm waves generated by T0709. The sand transport controls achieved by different types of coastal facilities were estimated and compared under an imaginary wave condition that could occur in future. A newly-designed groin with a low crown height was found to be most effective in preserving a straight coastline, if a sufficient amount mount of sand will be supplied by beach nourishment.
