This paper presents precise active floodplain and paleo floodplain mapping of the Palam Cauvery in its deltaic region implementing various Geospatial Techniques, as well as a comparative analysis to comprehend the changes that have occurred to the river course in the past. False Colour Composite (FCC), Normalized Difference Water Index (NDWI), Principal Component Analysis (PCA), Synthetic Aperture Radar (SAR) ALOS PALSAR L- Band and Digital Elevation Model of ALOS PALSAR has been used to carried out the detailed mapping. The active floodplain and paleo flood plains are mapped using the method proposed above and ten separate cross-sectional profiles were obtained along the river course, revealing that the paleo flood plain has an aerial extent that is 86% broader than the present flood plain. This clearly shows that the principal river was formerly running along the Palam Cauvery in this course and has progressively shifted or migrated