We urgently need to deepen our current understanding of the root causes of the environmental issues in terms of market failures, inadequacies in policy, governance and resources, and deficiencies in information. A profound interdisciplinary study, bridging social and physical science and integrating seas and associated land catchment areas, is required at a national, regional and global level. This should lead to practical measures to address the root causes of the problems themselves.

We live in a society governed in a very sectoral manner and although the ineffectiveness of this sector-by-sector approach has becoming apparent, a truly holistic approach is particularly lacking in the case of the atmosphere and international waters, the global commons. They are transboundary in nature but provide "free" goods and services to the economies of individual countries. Nobody really pays the costs of these services or seeks better practices to avoid using them. In the case of international waters, current usage of the natural systems is unsustainable and there is clear evidence for the decline in fisheries, coastal ecosystems, freshwater quantity and quality, and the quantity and quality of water in aquifers.

Causal chain analyses will be one of the important tools used for the Global International Waters Assessment. It will be essential to identify and better understand the causal chains between perceived problems and their societal root causes. When identifying a water-related problem one must clarify the environmental impact, the socio-economic impact, and the potential transboundary consequences.

The GIWA causal chain analyses will concentrate on five major problem areas of concern, initially divided into 22 major issues. The conditions in each area will determine which issues that will be considered relevant to address in that particular area:

Freshwater shortage
Modification of stream flow - Pollution of existing supplies - Changes in the water table

Pollution
Microbiological - Eutrophication - Chemical - Suspended solids - Solid wastes - Thermal - Radio nuclide - Spills

Habitat and community modification
Loss of ecosystems - Modification of ecosystems or ecotones, including community structure and/or species composition

Unsustainable exploitation of fisheries and other living resources Over-exploitation - Excessive by-catch and discards - Destructive fishing practices - Decreased viability of stock through pollution and disease - Impact on biological and genetic diversity

Global change
Changes in hydrological cycle - Sea level change - Increased uv-b radiation as a result of ozone depletion - Changes in ocean CO₂ source/sink function

A causal chain is a series of statements that demonstrate and summarize, in a stepwise manner, the linkages between problems and their underlying (root) causes. It will, thus, include immediate, secondary, tertiary, and quaternary causes, i.e., human activities leading to the creation of the problem. Uncertainties accompanying each linkage should also be clearly stated. The analysis also permits barriers to resolving the problems to be investigated.

A causal chain probes the linkages between the problem and its societal causes. In its practical application, it can serve as a model into which regionally relevant information may be inserted. When properly supported with quantitative information, the causal chain can be reversed and used to study the implications of different policy options in the improvement or worsening of environmental problems. Such an analysis may also be used to examine the effects of one policy decision on another, seemingly unrelated issues.

Some more concrete examples of causal chain analyses for identification of water-related major concerns and principal issues have been outlined in the GIWA Project Document.