Alistair Rieu-Clarke

The Mekong River Basin is shared between China, Myanmar, Laos, Thailand, Vietnam and Cambodia. The basin is central to the sustainable development of its population, whilst also being an important ecosystem in need of protection. Climate change adds greater complexity to the management of the basin. Since the 1950s, the countries of the lower Mekong Basin have cooperated. A key milestone was reached in 1995 with the adoption of the 1995 Mekong Agreement between Cambodia, Laos, Thailand and Vietnam. The Mekong Agreement sets out key substantive and procedural requirements for the parties to share the lower Mekong in an equitable and sustainable manner. These commitments are supported by the establishment of the Mekong River Commission (MRC), which has overall responsibility for supporting the implementation of the 1995 Agreement. While no explicit compliance and implementation mechanism (CIM) exists under the 1995 Mekong Agreement, the parties have demonstrated a willingness to exchange data and information, establish joint monitoring, develop a basin development strategy, and engage non-state actors within the basin. A major challenge related to the Mekong Agreement's compliance and implementation has been the development of hydropower projects. In particular, the implementation of the Procedures for Prior Notification, Consultation and Agreement (PNPCA) has proven problematic, but they have also provided important insights into how compliance issues within the context of hydropower developments of transboundary rivers are tackled.

At the global level, notable developments in the field of international water law include the adoption of the 1997 Watercourses Convention, and the opening of the 1992 Water Convention to all UN Member States as of 2016. At the regional level, two legal frameworks instruments have also promoted transboundary water cooperation, the 2000 EU Water Framework Directive, and the 2000 Revised SADC Protocol. Additionally, while not legal in nature, the SDG monitoring framework has been an important addition to assessing progress in the coverage of operational arrangements for transboundary water cooperation globally. Around 80% of countries sharing transboundary waters have submitted data to the SDG indicator 6.5.2 monitoring exercise, the results of which feed into UN decision-making processes related to sustainable development and transboundary water cooperation. Out of these framework instruments related to water, the reporting mechanism under the Water Convention is the most detailed in assessing the progress of parties in the implementation of the Convention. While only around a third of countries sharing transboundary waters are party to the convention, both the reporting mechanism and the implementation committee under the convention clearly show how such a framework instrument can support compliance and implementation within a transboundary water context.

Ever since a compliance and implementation mechanism (CIM) was incorporated into the 1987 Montreal Protocol, there has been a proliferation of such mechanisms within multilateral environmental agreements (MEAs). Given the complex nature of environmental problems, CIMs have proven to be a better means by which to manage MEA compliance and implementation compared to traditional dispute settlement mechanisms. While the design of CIMs varies from one MEA to another, they tend to include three core functions, namely reporting, reviewing and addressing weak implementation or non-compliance. In terms of reporting, MEAs include measures by which parties usually self-report on their progress in implementing an MEA, although some have options for non-parties to report or comment on the reports submitted by parties. Reviewing these reports is often left to the secretariat of the MEA. Additionally, compliance and implementation committees often play a key role in reviewing incidences of non-compliance or weak compliance. There are various ways in which such a committee may hear a case, including through self-reporting by a party itself, by one party raising an issue of another party, or through a ‘committee initiative’, i.e., where information is provided to the committee from other sources, such as from non-governmental organisations. In terms of addressing weak implementation or non-compliance in MEAs, the provision of financial and technical assistance might be the most effective means by which a party that is struggling to implement its commitments is supported.

An analysis of compliance and implementation within the context of transboundary water agreements requires an understanding of the broader context within which countries enter into agreements and comply with those commitments. Several cross-disciplinary perspectives explain why countries cooperate over transboundary waters. A realist perspective argues that power is the main factor influencing transboundary water relations. In such a scenario, it is suggested that where the most powerful country in the basin, i.e., the hydro-hegemon, is upstream, such as China or Turkey, they are likely to dictate cooperation. Where the hydro-hegemon is downstream, such as India and South Africa, they may be more willing to enter into cooperative arrangements in order to secure their interests. An additional perspective highlights the importance of incentives and reciprocity in promoting transboundary cooperation. Examples, such as the Senegal River Basin, the Columbia River Basin and the Catskills Watershed show how states generate more benefits from cooperation than they could ever achieve through unilateral action. A further body of scholarship emphasises the value of institutions in nurturing cooperation. Finally, the importance of norms and ideas in shaping state conduct is highlighted as an importance influence on transboundary water relations. Combined, these different perspectives offer important insights into why countries enter into transboundary water agreements in the first place, and once adopted comply with their terms.