Mapping rivers and preserving livelihoods

River scientists and marine geophysicists from the US and UK have teamed up for a unique collaboration that could help protect the lives of thousands of people who live close to the banks of some of South Asia's biggest rivers. Led by the University of Birmingham with the universities of Exeter and Southampton, and featuring input from academics at the University of Illinois at Urbana-Champaign and Vanderbilt University, the research is focused around the pinpointing of dramatic river features called megascours. Megascours are large depressions eroded into riverbeds that can be up to a kilometre wide and 50 metres deep, or the height of a 16-storey building. A common feature of rivers is that at bends, or where two channels join, they scour out their beds to depths that greatly exceed the average. In the world's largest rivers, such as those found in Bangladesh and India, these features are gigantic, due to the amount of water they discharge. For example, at peak flow, the Ganges-Brahmaputra-Meghna River system in Bangladesh - where the international team is focusing its research - discharges enough water every second into the Bay of Bengal to fill 64 Olympic-sized swimming pools. Research is being carried out by the team from a boat at targeted locations where the Brahmaputra and Meghna Rivers are at their most dynamic and have the greatest potential to erode their banks.