In 1950, only Arabian countries were facing water shortages. Now, 31 countries, accounting for nearly 8% of the world's population, are facing chronic freshwater shortages. In the next 25 years, chronic water shortage problems are likely to expand to West Asia, China, North Africa, Sub-Saharan Africa, and Peru. More than 2.8 billion people in 48 countries will face water stress or scarcity conditions by 2025. By 2050, the number of countries which will face water stress or scarcity could increase up to 54 and 4 billion people who may suffer from water shortages. The number of suffering people is equal to approximately 40% of a projected global population of 9.4 billion. The Asia and Pacific region constitute about 36% of global run-off.  Even so, water scarcity and pollution are key issues and the region has the lowest availability of freshwater per capita. Several countries, including Bangladesh, India, Pakistan and the Republic of Korea, already suffer from water scarcity or water stress.  More will be the same situation as populations and consumption increase.

Water problems in Asian countries are undoubtedly in a critical problem Japan is confronted with. Monitoring of water quality in most of the main rivers in Asia was conducted under the GEMS/Water Programme.  The Mekong River, the largest international river in Asia, was monitored of water quality by four riparian countries including Thailand, Lao PDR, Cambodia and Viet Nam during the period from 1985 to 1994; but the monitoring was discontinued in 1995.

To improve our understanding of the many changes and challenges affecting the ecosystem of the Mekong River, to predict long-term ecological changes, to develop appropriate and scientifically-based management plans, and to derive implementable solutions for realizing the sustainable development of the Mekong River, the following was decided: the long-term monitoring of the ecosystem of the river should be implemented under an international network of riparian countries in cooperation with Japan and the GEMS/Water Programme.  In 2003, NIES was requested to help and support the establishment of the long-term monitoring by riparian countries and the GEMS/Water office.