Countermeasure for wind‐blown sand at a nourished beach: an example at the Niigata west coast, Hiyoriyamahama beach

Souichi YAMAGATA, Toshihiro SHIMIZU, Akiyoshi KATANO, Haruo MORI and Shusei OGAWA


For beaches, the wind‐blown sand may need to be controlled in the region from the shoreline to the landward end of the dry beach to prevent sand transport by the wind from the beach surface, eroded, and subsequently deposited in unwanted areas. It was necessary to develop integrated countermeasures against windblown sand dispersal on the limited width of the beach nourishment. Therefore, a literature review was conducted focusing on effective measures to control windblown sand dispersal. The results showed that sand fences, sand trap trenches, beach earthworks, and vegetation are effective measures to control windblown sand on the beach. Sand fences, sand trapping trenches, and vegetation were selected as control devices to stop and stabilize blown sand generated in the seaward region of the beach. Then, a series of field experiments were conducted to examine the function of sand fences, trenches, vegetation, and combinations of these structures. The field experiments yielded the following results. 1) Sand fences functioned well if the sediment was removed before about 70% of its height was filled, 2) Two different sand fence arrangements were tested on a natural beach, which are a configuration that combines a straight line and a transverse alignment, and a configuration that combines a straight line and a perpendicular alignment. The former configuration was functionally superior, but the latter also worked well. 3) A rectangular trench with 1 m deep and 5 m wide also functioned well until the trench was filled. 4) Vegetation work with sand grasses did not trap as much blown sand as expected. 5) A combination of structures, vegetation, trench, and sand fences positioned from the shoreline was found to be effective in controlling blown sand.

Key words

wind‐blown sand, integrated countermeasure, nourished beach, sand fences, vegetation, trench trap