If urgent action is not taken, the Mekong Delta in Vietnam could be almost completely submerged by sea water by the end of the century. In an article published in Science, an international research team which includes Prof. Andrea Castelletti of the Department of Electronics, Information and Bioengineering of the Politecnico di Milano, has identified concrete actions to prevent this economically very important and densely populated area from drowning.
Most of the 40,000 km2 of the Mekong Delta is located 2 meters below sea level, therefore it is subject to rising oceans due to global warming. In addition, local actions such as the excessive pumping of groundwater, the extraction of sand for construction purposes and the rapid development of hydroelectric power, threaten the future of the most productive rice fields in Southeast Asia. The research team argues that only a coordinated action by the six countries in the Mekong basin (China, Laos, Thailand, Cambodia, Vietnam) and better water and sediment management within the delta could avoid such outcomes.
There is scientific evidence that identifies the processes that endanger the existence of the Mekong Delta and how these processes could be controlled and mitigated. The team identified six measures that would significantly increase the survival of the delta. Dams could be designed to allow for better passage of sediments (1), and strategically positioned to reduce downstream impacts, or replaced by wind and solar farms where possible (2). Sediment mining should be strictly regulated and the use of Mekong sand could be reduced through sustainable building materials (3). Intensive agriculture in the Mekong delta should be re-evaluated for its sustainability (4) and natural solutions for coastal protection should be implemented on a large scale along the delta coasts (5 and 6). All of these measures are feasible and have precedents in other areas of the world.
Despite the effectiveness of these measures, especially if implemented in unison, there are important obstacles to their implementation. Some of these actions would conflict with the vested interests of certain local players, such as the sand mining industry and hydroelectric power plants. The measures would require coordination between countries, which would have to agree that the sustenance of the Mekong Delta is an important goal of regional policy.
The implementation of the measures will require the participation of national governments and international actors (banks and development agencies), as well as new actors, such as the private sector and civil society.