Monitoring dam stability using psi and sbas analysis

Water preservation and maximization of its efficient use is key in areas facing water scarcity like California. One of the most important resources available to us are dams, which are useful to address a variety of needs like water supply, flood control, and maintaining environmental flows. However, if not managed properly, dams can be disastrous to humans and wildlife alike, different water species, habitats, and even impact water quality for a region. In this context, we have used newer Synthetic Aperture Radar Interferometry techniques like Persistent Scatterer Interferometry (PSI) and Small Baseline Subset (SBAS) to estimate the displacement rates at Shasta Dam in California, USA, and compare between the two techniques. Our results indicate that both the analyses show similar displacement trends, however, they differ in the magnitude of the displacements. The varying displacement values can be attributed to fundamental differences in the way both these techniques analyze data.