Mizushima island located in Tsuruga Bay is a famous recreational beach in Fukui Prefecture. This beach has been eroded in recent years. The topographic changes and tide level changes at Tsuruga Port were measured. On the basis of these field data, the contour-line-change model proposed by Noshi et al. was applied to the prediction of beach changes. It was concluded that beach changes closely relate to the wave action along with the increase in tide level during passage of low pressure in summer.
