Abstract
The siltation mechanism in power plant basin located at silty coast in southern shore of the Suo-nada sea was investigated by topographic survey and numerical analysis. Two patterns are recognized in annual depth change to characterize the siltation mechanism in this site. One of them is flat silting at navigation and anchorage area mostly occurs in usual wave condition. Another pattern occurs in annual depth change with tough wave condition which characterized with erosion at navigation area and concentrated silting in trench for cooling water intake the innermost area in the basin. These depth change patterns were described by numerical model. In the second pattern, influence of the density current created by suspended sediment with high concentration was suggested.
