Author(s): Hitoshi Tanaka; Mohammad Bagus Adityawan; Hisao Nagabayashi
Linked Author(s): Hitoshi Tanaka
Keywords: Tsunami; River mouth; Morphology changes; Water level; Tidal level; Aerial photo
Abstract: The morphology changes of the shoreline and the river mouth around the Samegawa River, after and during its recovery following The Great East Japan Tsunami of 2011, were investigated in this study by analyzing the aerial photos and water level data. The aerial photos provide valuable information on the changes. It was found that the sand spit and sandy coast in the north of the Samegawa River mouth were severely eroded. More detailed analysis based on water level data was conducted to investigate temporal variation of the river mouth condition. The correlation coefficient and the linear gradient between the water level data in the river and the tidal level were analyzed. The river mouth narrowing, as well as the river mouth opening has been successfully detected. The assessed parameters correspond well with the condition obtained from the aerial photo analysis when available.