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Land subsidence, when land sinks or caves, can occur when water or other fluid (such as natural gas) is withdrawn from the ground, creating instability in the rock structure below. As a result, the ground can shift and cause sinkholes, uneven ground and changes in land surface altitude. Interferometric Synthetic Aperture Radar (InSAR) satellites offer the opportunity to get a millimetre-accurate measurement of the subsidence of cities and the buildings and infrastructure within it. As satellite images cover an area of 30x50 km up to 200x800 km, city-wide measurements can be completed cost-effectively allowing cities to use a data-driven, fact-based approach to subsidence and its effects on water management and utility performance. InSAR can also be used to complete damage assessments of sewer and utility networks, which are directly influenced by subsidence. It can also be used for monitoring groundwater, sensing seismic activity, and assessing ice sheet movement and permafrost melting. A spin-off application of the data lies in use for civil engineering projects (e.g. building pits and underground construction) in the city, which can make use of the same measurement data.