The Stung Treng Ramsar Site in northeastern Cambodia is one of the Mekong River’s most important—and most threatened—flooded forest ecosystems. Our Southeast Asia team and IUCN teamed to develop a new report, Dam‑Induced Flow Alterations and Habitat Loss in Cambodia’s Stung Treng Ramsar Site, which shows how upstream hydropower operations have fundamentally altered dry‑season river flows, driving widespread forest die‑off and erosion in a system that depends on seasonal low water to survive.
Combining hydrological analysis, satellite‑based dam operations tracking, remote sensing of land and vegetation change, and community observations, the report documents an 18 percent loss of flooded forest since 2018, with some hotspots losing more than half their land and tree cover. These ecological changes are closely linked to dry‑season water releases from large dams in China and Laos that now keep river levels unnaturally high for months at a time.
Beyond local impacts, the findings raise broader questions for transboundary river governance, data transparency, and the geopolitics of hydropower in the Mekong Basin. The report also outlines feasible operational adjustments that could help restore critical low‑flow windows without undermining regional energy security.
Join us for an upcoming webinar from to hear the findings, explore their policy implications, and discuss what this case means for river conservation and cooperation in an era of intensifying geopolitical competition.
Photo courtesy of Andy Ball.
Featured Speakers
Brian Eyler, Southeast Asia Program Director, The Stimson Center
Brian Eyler directs the Southeast Asia Program and the Energy, Water, and Sustainability Program. He is an expert on transboundary issues in the Mekong region and specializes in China’s economic cooperation with Southeast Asia. He is widely recognized as a leading voice on environmental, energy, and water security issues in the Mekong. Brian is co-lead on the Mekong Dam Monitor. His first book, Last Days of the Mighty Mekong, was published by Zed Books in 2019.
Jake Brunner, Head for the Indo-Burma Group, International Union for Conservation of Nature (IUCN)
In his role as IUCN’s Head of the Indo-Burma Group, Jake covers Vietnam, Cambodia, Lao PDR, Thailand, and Myanmar. Before joining IUCN in 2008, Jake spent eight years running Conservation International’s Indo-Burma Program from Washington, DC, Hanoi, and Phnom Penh. Previously, Jake spent eight years at World Resources Institute, an environmental policy research center in Washington, DC. He holds a BA in Geography from Oxford University and a MS in Remote Sensing/GIS from
Kathryn Bimson, Programme Officer for Water, Wetlands and Nature-based Solutions for Climate, IUCN (Moderator)
Ms. Kathryn Bimson has been working on wetlands in Southeast Asia for the last nine years, and is currently coordinating the regional implementation of a number of projects related to Nature-based Solutions and wetlands in the Lower Mekong Basin. Ms. Bimson also supports the Secretariat for the Indo-Burma Ramsar Regional Initiative, working closely with the governments of Cambodia, Lao PDR, Myanmar, Thailand and Viet Nam to strengthen the implementation of the Ramsar Convention in the region.
Courtney Weatherby, Southeast Asia Deputy Director, The Stimson Center (Moderator)
Courtney Weatherby’s research focuses on sustainable infrastructure and energy challenges in the Indo-Pacific, particularly at the nexus of issues in food, water, and energy in the Greater Mekong Subregion. Weatherby was a lead author on a range of technical and policy studies with Pact Thailand and IUCN on hydropower investment and regional electricity trade and supports the Mekong Dam Monitor.