[This paper first reviews the role of international law in the governance of international watercourses, including the role of the principle of equitable utilisation. Discussion then turns to a suggested logical corollary to the principle of equitable utilisation: a principle of equitable sharing of downstream benefits. The situation with regard to the equitable sharing of downstream benefits on the Columbia River is discussed together with other examples. Consideration follows of the possible application of the principle of equitable sharing of downstream benefits to help resolve conflict in other international watercourses including the Karnali and the Mekong. The paper concludes that there is a role for an emerging principle of equitable sharing of downstream benefits in helping to turn historical adversaries into partners.]CONTENTS I Introduction II International Water Law III The Principle of Equitable Utilisation IV The Columbia River and the Equitable Sharing of Downstream Benefits V Downstream Benefits VI The Karnali River (Nepal/India) VII The Mekong River (China/Myanmar/Thailand/Cambodia/Laos/Vietnam) VIII Turning Adversaries into Partners
There are currently at least 250 international watercourses in the world shared between two or more sovereign nations, (1) In many of these sovereign nations water resource development is considered a critically important vehicle both to help alleviate poverty and to stimulate economic growth. (2) Many of these nations also wish to obtain economic benefits, including those from flood control, irrigation and hydropower development activities. (3) This paper has three objectives. The first is to review briefly the development of the fundamental international water law principle of `equitable utilisation'. The second objective is to identify and review a suggested logical corollary to the principle of equitable utilisation, namely an emerging principle of equitable sharing of downstream benefits, by considering experiences in relation to the Columbia River and elsewhere. The third objective is to apply the principle of equitable sharing of downstream benefits to the Karnali (Nepal/India) and Mekong (China/Myanmar/Cambodia/Laos/Thailand/Vietnam) international watercourses, to assess the potential usefulness of the principle in assisting to resolve longstanding conflicts between upstream and downstream states, and in helping to turn historical adversaries into partners.
II INTERNATIONAL WATER LAW
International water law belongs to the field of public international law that deals primarily with the non-navigational uses of international watercourses. (4) International law in general is composed of decisions about events that have effects on more than one state or entity, and provides expectations about how states are expected to behave in particular circumstances. (5)
The `principle of equitable utilisation' is generally considered to be the fundamental principle of the law of the non-navigational uses of international watercourses. (6) This principle is enshrined in both the Helsinki Rules and the UN Watercourses Convention. (7)
III THE PRINCIPLE OF EQUITABLE UTILISATION
The principle of equitable utilisation requires states to act reasonably and equitably when dealing with transboundary water resources in their territory. It requires that the reasonableness of any utilisation is to be determined by weighing all relevant factors and by comparing the benefit that would follow from the utilisation with...