Mutual Evaluation of Beach Erosion Control in JAPAN,EC,USA

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Scientific understanding of how natural beaches mitigate storm energy has now become the basis for the consideration of beaches as soft shore protection structures by the coastal engineering profession. Focusing on the beach nourishment projects, own shore protection strategies in JAPAN, USA and EU has been evaluated by mutual survey. The main results obtained are :EU case : The beach fill situation in the countries of the European Union is highlighted and discussed with respect to the general situation, project type and objectives, design and evaluation procedures, legal framework, and financial aspects. As expected, significant differences were found between the investigated countries. In general, the study shows that it would be very profitable for south European countries to learn about the Dutch and German practices, particularly regarding the long-term coastal management and the regular monitoring of the coastal morphology. On the other hand, recent Dutch experience has shown that their legal system is a bit too rigid leading to automatic local renourishments that are unnecessary to reach the global objectiveUSA case : A 1971 study by the US Army Corps of Engineers found 2600 miles (4200 km) to be experiencing critical erosion. Between 1 950 and 1 995 the Corps constructed 56 large shore protection projects that covered 210 miles (340 kin) or about 8 percent of that eroding. In 1970, a shift from hard structures (20%) to soft structures (80%) as beach nourishment occurred that continues today. Actual construction costs to 1993 totaled $670 million or about $15 million per year. In 1995 dollars ; adjusted costs were $1,580 million or $34 million per year. The total volume of sand placed was about 1 90 million cubic yards (cy) for the 49 projects that involved beach nourishment. Average unit sand cost was $3.55 per cy.