Reclamation Effect of Tsunami Height and Velocity in the Shoreline

Abstract

Indonesia is a country flanked by 3 active plates and has many active volcanoes. This condition makes Indonesia susceptible to tsunami disaster. In 2018 Indonesia was hit by two tsunamis. The cause is plate friction and volcanic activity. Tsunami waves have a unique characteristic, the height of a tsunami wave in the middle of the sea is the same as ordinary waves, but when it reaches the shoreline the height gets higher. The reason is the increasingly sloping coastal contours. Coastal contours in Indonesia generally changes, either naturally due to abrasion and erosion, or artificially like reclamation. Reclamation clearly impacts the slope of the coast, causing different tsunami heights. This study discusses the impact of Reclamation on tsunami heights. Using the TUNAMI Mathematical Model, the results obtained are the height of the tsunami at the shoreline before Reclamation of 0.80 and the speed of 63.4 km / h, while the height of the tsunami after Reclamation is 0.87 and the speed is 70.5 km / h, so that the impact of Reclamation on the height and speed of the tsunami increases 8% and it can be concluded that the effect of Reclamation on tsunamis is to increase the risk of damage.