High water flow in the Brahmaputra River in Bangladesh in July 2017
High water flow in the Brahmaputra River in Bangladesh in July 2017. During the monsoon season, the Brahmaputra floods inside Bangladesh with water flowing from India and China, an event known as a transboundary flood. Credit: Faisal Hossain
When Floods Cross Borders, Satellite Data Can Help
(15-Feb-19) On 23 July 2018, a dam in southernmost Laos collapsed, and the resultant flood left more than 6,000 people homeless. The fractures in the dam that led to the disaster were discovered 2 days earlier. Yet the residents who lived downstream, many across the border in Cambodia, didn't have access to real-time information about the increased risk of flooding. Such floodwaters that cross borders are often termed "transboundary floods" and are more likely to be catastrophic. News such as dam-driven flooding in Laos underscores the urgency of making information on upstream dams in transboundary regions more accessible to citizens of developing nations. In a bid to improve timely access to upstream reservoir information in transboundary river basins of the Red and Mekong rivers, Vietnam recently launched a satellite-based operational system. This article describes the key steps to building such a transboundary dam monitoring system for water agencies of developing countries.