Ecosystem services and international water law: towards a more effective determination and implementation of equity?

Interest in an ecological- or an ecosystem-centred approach to natural resource management is not new, and in the case of water management has been very well emphasised for many decades. Recently however, a new focus has emerged around the identification and assessment of ecosystem services, and the potential to somehow use valuation of these services as a basis for more effective management of natural and human-linked systems. Despite this growing recognition, attempts to apply such an approach to transboundary watercourses are few and far between. While key principles of international water law, for example, equitable and reasonable utilisation, are not in conflict with an ecosystem services approach; significant challenges remain in its implementation. However, as the methods and tools used to identify ecosystem services improve, it is likely that such an approach will offer an important means by which to reconcile competing interests over shared watercourses in the future.