Determining relationship between river path changes and flooding through alignment of historical and current maps

Abstract

This study proposes the use of image processing techniques to compare and detect changes that have occurred on the river paths shown in an 1898 Manila map and its corresponding current map. We focus on Pasig River along Quiapo and San Miguel. Piecewise linear image transformation is used to align the area and water channels of the two maps. The changes that have transpired are visually inspected and automatically detected using color image segmentation and image subtraction technique. The method is applied to a flood hazard map to determine a relationship between the evolution of river channels and flooding. The introduced process should provide information in the vulnerability of an area to flooding and other hazards.