Mapping a pollution index for the transboundary Red River Valley, Asia, 2009–2011

Abstract

A transboundary river is a river that flows through two or more countries. Due to the international policies of the government in each country, it is difficult to investigate the pollution conditions in a transboundary watershed. In this study, pollution sources in the Red River Valley, Southeast Asia were derived from Google Earth by visual interpretation. Based on the derived pollution sources and a simple scoring system, a pollution index map was produced, which provides useful information for intergovernmental cooperation on the water environment in this transboundary watershed. In addition, the method mentioned in this article suggests an efficient and low-cost way to investigate pollution conditions at large scale, which can also be applied to other transboundary watersheds in the future.