The contribution of procedural rules to the environmental protection of transboundary rivers in light of recent ICJ case law

Any frank analysis of the role of procedural rules of international water resources law in the environmental protection of transboundary rivers and aquatic ecosystems must inevitably lead one to conclude that such rules perform an absolutely central function. Despite the fact that in the Lac Lanoux case an international arbitral tribunal could confirm as early as 1957 that the key customary obligation imposed upon a State planning a project to utilize shared water resources was that of notifying the co-riparian States likely to be affected, much of the intellectual and diplomatic energy since expended in this field has focused on the broader, and rather more nebulous, substantive principles that apply, including those of equitable and reasonable utilization and prevention of significant transboundary harm. While such substantive principles provide a broad framework for identifying the shared values of States that underpin and give direction to efforts to avoid or resolve disputes over international water resources, it is the procedural rules which require the exchange of information so vital to any meaningful inter-State engagement.