Journal Article

Alarm over a sinking delta

Schmidt, Charlie

2015

Overview

Rise and Fall project seeks ways to slow land subsidence in Vietnam's populous Mekong delta. Vietnam's Mekong River delta—the world's third largest delta—is sinking, putting some 20 million people and vast swaths of fertile farmland at risk. Recent research has found that the delta, which covers some 55,000 square kilometers and sits about 2 meters above sea level, is subsiding at rates of 1 to 4.7 centimeters per year. Among the culprits: levees that prevent sediment from spilling out of rivers and collecting in the delta, and some 1 million wells drilled since the 1980s for drinking and agriculture. If groundwater depletion continues at present rates, researchers estimate, the delta could sink by nearly a meter by midcentury. Now, an alliance of Vietnamese and Dutch scientists is trying to get ahead of the problem. They met in Vietnam recently to launch the Rise and Fall project, a $1 million, 5-year effort to better understand what's driving Mekong delta subsidence and develop strategies to reverse it. \"We know virtually nothing about what's beneath our feet,\" said geographer Philip Minderhoud, a co-leader of the project and doctoral candidate at Utrecht University in the Netherlands, during the 11 March gathering. New studies aim to change that.

• Publisher: The American Association for the Advancement of Science
• Subject: Agricultural land / agriculture / at-risk population / Deltas / drinking water / Ground-water depletion / Groundwater / Groundwater depletion / Launches / Levees / Levees & battures / Measuring instruments / Mekong River / Meters / people / risk / river deltas / Rivers / sediments / Subsidence / Vietnam / wells