Dear Eos:
As the annual monsoonal flood pulse started to rise on the Mekong River in June 2025, our team from the University of Southampton (Julian Leyland, Steve Darby, Gustavo Nagel, and Chris Tomsett), working with Cambodian colleagues including Vutha Srey, undertook multibeam sonar surveys of a reach of the river near Roka Koang, Cambodia.
As part of the HIDDEN SAND (Holistic Investigation of the Distribution, Extraction, and Networks associated with SAND) project, we’re quantifying how sand mining is reshaping the riverbed and how it affects the local community. In this photo by Andy Ball, also of the University of Southampton, our survey vessel is off camera to the right as it passed close to two sand barges traveling downstream to local and global markets in Phnom Penh.
—Steve Darby, University of Southampton, Southampton, U.K.