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During the past 10 years, Timor-Leste has concentrated all its efforts on infrastructure development. However, it has not achieved enough due to unexpected ground deformation in mountainous areas that is seriously affecting road constructions, etc. In order to design roads and other infrastructure under such difficult conditions, it is important to know the present and future ground conditions. Continuous monitoring is a significant methods of detecting ground deformation and providing essential information to realize an effective design. The problem arises of “How can ground deformation be monitored in extensive areas, which are generally located in mountain areas that are difficult to access?” Differential Interferometry Synthetic Aperture Radar (DInSAR) has recently been applied to monitor displacement in extensive areas. In addition, Unmanned Aerial Vehicle (UAV) photogrammetry is useful for detecting the deformation in detail. Both methods are advantageous in that they do not require any sensors. Therefore, the combination of DInSAR and UAV photogrammetry is one of the solutions for monitoring the ground deformation in Timor-Leste. In this paper, DInSAR and UAV photogrammetry are applied to unstable ground in the Bobonaro region of Timor-Leste to find the recent ground deformation, since 2007, due to earthquakes and hard rainfall events. It is found that DInSAR is useful for screening usual and unusual ground behavior and that UAV photogrammetry is flexible to use and can detect displacements with cm accuracy after the DInSAR screening.

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The world population percentage placed Indonesia in fourth place of the highest populated countries in the world. The majority of Indonesians live in an urban area. Java Island is the highest populated island in Indonesia, especially in Jakarta, Semarang, and Surabaya. This study showed the flood depth in these three cities, which has become a yearly threat during the rainy season. At the same time, another problem due to water withdrawal was analyzed. Land subsidence has occurred due to simultaneous water withdrawal and overload of alluvial soil due to land-use conversion. A remote sensing data and geographical information system (GIS) took account in this analysis to achieve the aim of this study. The hydraulic model was created to produce a flood depth map, and differential interferometric synthetic aperture radar (DInSAR) technique generated a land subsidence map. This study aims to show the problem in these three cities related to water in urban areas. This study found that all study areas had a severe risk of flood and land subsidence. Semarang received more threats to flood and land subsidence comparing to the other cities.

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