"Long swell" which attacked Toyama Bay from February 23 to 24, 2008, serious damaged breakwaters at FushikiToyama Port. We used the wave prediction model which considered data assimilation to predict offshore wave. And we calculated wave transformation in a shallow water using Boussinesq-type wave transformation model (NOWT-PARI for short). We combined these both of them and built the prediction model of "Long Swell" at Fushiki-Toyama Port. To improve the precision of the made prediction model of "Long Swell", we built the wave watch system. We showed that a prediction of "Long-Swell" is possible to use wave prediction model and a wave watch system.

The reliability-based design method is the standard design method for the technical codes for port facilities. Determination of target failure probability is very important on the reliability-based design. In this study, the sliding failure of the caisson type breakwater (composite type breakwater and breakwater covered with wave-dissipating blocks) is treated in view of sliding displacement. First, survey of the latest design wave condition including extreme probability condition is conducted. Characteristic of design wave condition in each area is analyzed. Next, failure probability for caisson type breakwaters designed by conventional design method is estimated in view of sliding displacement. Finally, target failure probability is optimized in order to apply the reliability-based design to practical design using the latest design wave condition.

Stabilization of the seawalls is required for protecting the important facilities along the coast of the Fukui Port. Since 2004, Ministry of Land, Infrastructure and Transport has commenced the projects for improvement of the existing seawalls for scouring and liquefaction protection, and for construction of new submerged breakwaters. Construction of "t wo-crested submerged breakwaters," which have two parallel crests along the coast, was newlycommenced in 2006. The ministry realized that stability of the submerged breakwater needs to be examined because the submerged breakwater experiences winter stormy waves while the construction of the breakwater is not yetcompleted, i.e.,the total length of the breakwater is 45m compared to the designed total length of 200m. This paper presents a survey result of location of concrete armor blocks for the submerged breakwater on partial completion with using Real-Time-Kinematic GPS.