Deformation monitoring around dam and reservoir in Indian Himalayas using SBAS-InSAR method

Abstract

Deformation monitoring of dam infrastructure and slopes surrounding the reservoir is essential for the maintenance and sustainable operation of the dam. Interferometric Synthetic Aperture Radar (InSAR) based monitoring is a promising remote sensing geospatial technology for effective monitoring of dam structures and reservoir rims with an accurate measurement of displacement at mm-level accuracy. In this study, the SBAS-InSAR method was used for data processing, and monitoring deformations at a dam and its reservoir rim, located in the Indian Himalayas. We found several sites around the reservoir having a noticeable mean line of sight deformation rate of 30 mm/yr to -30 mm/yr for ascending and +45 to -45 mm/yr for descending orbit. Results demonstrate a trend of deformation at the dam body and cumulative Line of Sight (LOS) deformation values reach up to -40 to +40 mm.