Land Subsidence Characteristics in Bandung City, Indonesia as Revealed by Spaceborne Geodetic Techniques and Hydrogeological Observations

Bandung, the capital city of West Java Province, Indonesia has been subsiding as reported by a series of Global Positioning Systems (GPS) observations and field evidence. In this work, an integrated satellite-based approach has been adopted using DINSAR and GPS observations to spatially delineate the subsidence-affected areas and cross-validate the subsidence rates using two collateral geodetic techniques. Multi-frequency DINSAR using C- and L-band SAR data facilitates to monitor land subsidence scenario in totality. C-band DINSAR has been found particularly useful to identify slowly subsiding areas with a sub-centimeter level of precision. Furthermore, the initial hypothesis that land subsidence in Bandung Basin has been occurring due to excessive groundwater withdrawal has been established in this study. A predictive modeling approach has been adopted to estimate the rates of potential subsidence due to elastic and inelastic deformations of the aquifer and overlying strata in response to the lowering of groundwater level.