The Project:
• Why SEA-BASINS
• Implementation
• Partner Network

NAGA
• Strategy
• SE Asia Models
• Informatics

Active Basins
• Mekong Basin
• Sub-basins

• Restricted Papers
• Restricted Data

Why SEA-Basins?

The extraordinary pace of development and population growth in Southeast Asia has placed dramatically increasing pressure on river basins and their downstream coastal ecosystems. The impact on river systems occurs through erosion of the land surface, changes in the nature of the sediment and its associated organic matter, and nutrient content from agricultural and urban sources. Changes in hydrology are immediate consequences of dam construction and large-scale water diversion for irrigation. Longer-term changes in regional weather patterns and climate will result in altered flow regimes and thus impact downstream ecosystems including the coastal zone. Coastal ecosystem production relies very strongly on material inputs from the land. Deterioration of water quality, due to natural causes such as salt and acidity, and anthropogenic causes such as domestic, agriculture and industry, is problematic in most if not all countries in this region. These changes have major consequences for economic opportunities and hence are risks for investments.

In the face of inevitable pressures on the environment, resources must be allocated and utilized with a higher degree of precision than they are currently. The sustainable use of water and land resources in Southeast Asia will require increasingly sophisticated information on the functioning of water flow systems and how they are affected by socio-economic and political institutions. One of the most serious problems for policy makers at regional, national and local levels in Southeast Asia is to maintain sufficient freshwater supply for increasing demand. Decisions about the usage and allocation of natural resources are generally made according to economic and political criteria. Policy makers frequently face conflicts among different interested groups, especially when a new development is proposed. Construction of large dams and irrigation megaprojects are clear examples where developers, environmentalists, local communities and water users conflict with each other.

Without an accurate understanding of the linkages between water resources and its controlling factors as well as the inability to forecast quantitatively the individual and combined impacts of such factors, most problems remain and conflicts are not settled. As these resources are frequently distributed across multiple physical and political boundaries, it is imperative that a suitable paradigm be developed that can guide their more sustained use. Contemporary policy and laws are sparse on quantitative criteria with which complex tradeoffs can be evaluated. The sound management and optimization and hence sustainable use of water and land resources will require increasingly sophisticated information on the functioning of water flow systems and how they are affected by socio-economic and political institutions. A template where decision-makers can consider rigorous scenarios of alternative futures could play an important role in making complex environmental decisions.

This requires an accurate understanding of linkages between water resources and its controlling factors, and the ability to quantitatively forecast individual and combined impacts of demand with sufficient detail to be relevant on a broad geographic base. Contemporary "Earth System Sciences," with their emerging capabilities in spatial and dynamic modeling coupled to such sophisticated observation systems as satellites, are now poised to provide a bridge from the basic science of large-scale river basins to the improved management of these resources. Because these studies involve how the Earth is changing, they are built on the "first-principles" of how systems function. Hence they are well structured for developing the type of scenarios that basin planning requires, as opposed to, for example, more traditional statistical approaches. The process must involve not only the scientists building the models but the policy makers and the citizenry of the region who will use it and be affected by it.

SEA-BASINS is being constructed to address these issues, using the capabilities of earth system sciences, and building on the network of expertise across the region.