Effectiveness of Eco-Friendly Design Options in Pacific Island Nations
Several countries suffer from rising sea levels which aggravate beach erosion and wave overtopping. Many Pacific island nations including Tuvalu are faced with the threat of disappearing as rising sea levels cause beach erosion. For this reason, countermeasure designs are needed to prevent this. It is difficult to build sturdy constructions on Pacific islands due to their locations far from developed countries which makes installation difficult. Moreover, Pacific island nations have low wave energies making soft techniques suitable as countermeasures. Eco-friendly designs that use the soft technique, and which also do not ruin the landscape, can be chosen as a design technique for these areas. Various economical and eco-friendly soft techniques using locally produced materials were applied in this study to protect against possible damage from erosion as well as overtopping. Hydraulic model tests were conducted to evaluate the effectiveness of these designs. In eco-friendly designs, locally produced sand and gravel nourishments and gravel bags using locally produced gravel were compared through hydraulic model tests. Gravel nourishments showed good results as a countermeasure when using the wave characteristics of Cyclone Ula, which has a 10-year return period; however, gravel dunes formed on the backshore which might spoil the aesthetics of the shore. The results of gravel bags along with sand nourishment showed a relatively good level of protection and additionally it can prevent gravel from moving around and spoiling the aesthetics of the shore.
KeywordsGravel Bag Gravel Nourishment Pacific Island Global Warming Coastal Erosion
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