Archive for the ‘International Water Law’ Category

Swimming Against the Current: Revisiting the Principles of International Water Law in the Resolution of Fresh Water Disputes

Wednesday, April 22nd, 2020

The following essay by Tamar Meshel, of the University of Alberta Faculty of Law, summarizes her recently published article in the Harvard International Law Journal under the same title. She can be reached at meshel [@]

Dr. Tamar Meshel

There are currently two dominant views in the international water law (IWL) literature on the relationship between the customary international law principles of ‘equitable and reasonable utilization’ (ERU) and ‘no significant harm’ (NSH). The first view considers ERU to be the guiding principle of IWL and subordinates NSH to it, while the second view posits that the two principles are equal, and neither prevails over the other. Both views may be fit for purpose in the daily management of interstate fresh water resources and the prevention of disputes. In the context of resolving ever-increasing transboundary fresh water disputes (TFDs), however, the practical application of the two principles remains unclear, casting doubt on their ability to effectively guide states. This is evident, for instance, in the ongoing dispute between Ethiopia and Egypt concerning the Grand Ethiopian Renaissance Dam. While Ethiopia claims an equitable and reasonable right to build the dam, Egypt maintains its historic right to be free from significant harm that it claims the dam will cause it. The unclear relationship between the two principles thus enables states to cling to contradictory interpretations that suit their unilateral interests, thereby aggravating the dispute rather than resolving it.

In my article, I explore the potential for NSH to operate as the guiding principle of IWL and promote the resolution of TFDs. The strengths and weaknesses of ERU, as well as the historical evolution of both ERU and NSH, have been discussed in detail elsewhere. The article therefore largely takes the status quo described above as its starting point, and focuses on how the role that the two principles have played in the resolution of TFDs could be strengthened. Its contribution is not in arguing that ERU is an irrelevant principle to TFD resolution. Rather, while ERU remains the end goal of such resolution, the article posits that, both conceptually and practically, the means to this end is the NSH principle.  

The article discusses two qualities of NSH that make it an appropriate guiding principle in the resolution of TFDs: First, its due diligence standard of conduct and second, its ability to balance states’ competing interests.

The due diligence standard of the NSH principle guides states on how to prevent or minimize the risk of significant harm. This standard can facilitate the resolution of TFDs since it does not simply impose an “amorphous negative duty” to avoid harm, but rather a “positive duty to take concrete steps” to prevent harm. It therefore makes such harm not only more easily attributable to a particular state, but also less likely to occur if diligence is exercised. The due diligence nature of NSH also clarifies that this principle does not constitute a rigid blanket prohibition of all harm, but rather a more flexible rule that enables states to prevent significant harm by requiring them to observe a basic and uniform standard of conduct.

In addition, the NSH principle can be used to objectively evaluate states’ competing water uses by way of a balance-of-harms analysis. This analysis weighs the overall detrimental effects of a particular water use against its overall benefits—or, in other words, the harm caused by prohibiting it. It achieves a balanced outcome by focusing on the relevant states’ mutual goal of avoiding the greater harm to each other, the environment, and the shared fresh water resource. The question guiding this analysis, moreover, is not whether a particular use is “equitable and reasonable” and should therefore be allowed regardless of the resulting harm, but rather what is the greater harm to be avoided—that caused by the particular use or that resulting from the loss of its benefits. This ensures that even where “equities presumptively [support] protection” of a particular use, “the balance of benefit and harm” is maintained.

The due diligence nature of NSH and its balance-of-harms analysis also operate to reduce the incredibly high transaction costs involved in the resolution of TFDs. Due diligence obligations contribute to the reduction of these transaction costs since they equip states with the common goal of preventing the greater harm, as well as with the tools to achieve it. The balance-of-harms exercise provides states with reciprocal protection as well as an objective yardstick with which they can evaluate each other’s behavior. NSH can therefore serve to reduce transaction costs arising from contradictory positions and the absence of a unifying, objectively assessable, guiding principle.

The article also evaluates the use of NSH and ERU in the resolution of TFDs in practice by analyzing six such disputes submitted to arbitration and judicial settlement. This analysis reveals that where only the ERU principle was applied by the court or arbitral tribunal, namely in the Danube River decision, the dispute was not successfully resolved. The absence of both principles in the Meuse River decision also did not lead to a successful resolution. In contrast, in the four disputes that were successfully resolved—Lake Lanoux, Indus River, San Juan River, and Uruguay River—the NSH principle was applied either alone (in the first three cases) or together with the ERU principle (in the latter case). This analysis is not intended to prove that the use of the NSH principle necessarily leads to the successful resolution of all TFDs, as such resolution ultimately depends on states’ political will and good faith. Nevertheless, it lends some empirical support to the conceptual proposition that NSH is well suited to guide states toward successful resolution.

In their current state, the ERU and NSH principles fail to provide effective guidance to states faced with TFDs. At the same time, these disputes are likely to continue arising around the world, making effective international rules even more imperative. This article suggests an alternative to the prevailing views of IWL, which treats the NSH principle as its guiding principle for the purpose of TFD resolution. This approach builds on NSH’s due diligence standard, and proposes a balance-of-harms analysis to assist states such as Egypt and Ethiopia in weighing their competing interests and minimizing or preventing the most significant harm. Using NSH in this way promises to achieve both harm prevention and equitable and reasonable use––the dual goals of IWL.

The full article can be accessed here.

Data Innovations for Transboundary Freshwater Resources Management: Are Obligations Related to Information Exchange Still Needed?

Monday, March 9th, 2020

The following essay by Dr. Christina Leb is a summary of her recently published monograph (under the same title), which appears in Vol. 4.4, 2019, pp. 3-78, of Brill Research Perspectives in International Water Law. Dr. Leb is a Senior Counsel at the Environment and International Law Unit of the World Bank and a Research Fellow at the Platform for International Water Law housed by the Faculty of Law at the University of Geneva. She can be reached at cleb[at]

Cross-border data and information exchange is one of the most challenging issues for transboundary water management. Water data is deemed sensitive and subject to restrictions with respect to dissemination and use in many countries. Another key challenge is the steady decline of ground monitoring systems due to ageing equipment, and the limited availability of resources for maintaining and modernizing these systems according to the latest standard of technology. At the same time, data and information availability is key to sustainable water management.

The 1997 United Nations Watercourses Convention (Art. 9) and the 2008 Draft Articles on the Law of Transboundary Aquifers (Art. 8) identify regular exchange of data and information as one of the general principles of international water law. The availability of information with respect to hydrological, meteorological, hydrogeological and ecological nature of transboundary water systems, among other, is required to implement the principle of equitable and reasonable utilization. States need to know about the natural characteristics of as well as the demands and stresses on the cross-border water system they share with their neighbours.

The main difficulty for riparian states is to obtain all the information and data required to prepare a detailed assessment according to the equitable and reasonable use principle. The information needs are wide ranging and often, not all information is available at the national level.

New opportunities for access to water related data have opened up with the availability of technological innovations related to real-time data, space technology, and Earth observation. These technologies have led to a drastic increase in quality and availability of hydrological, meteorological and geo-spatial data. In basins where seasonal flows are largely dependent on snow pack, satellite imagery of snow cover can help identify how much and where water is stored in the upper catchments. Information on lake and river surface elevation can facilitate downstream flow predictions. Field-based data sources can be combined with satellite data to further enhance forecasting and planning systems. With the help of telemetry, data can be collected even at remote, inaccessible places and automatically transmitted to central control points, where this data can be converted for various applications, such as flood forecasting systems, warning systems on toxic water pollution, and others. Hydro-meteorological models based on real-time and historic datasets can be used to shorten lead-time and enhance the accuracy of early warning systems.

The key legal drivers making Earth observation data more available come from outside international water law. Space law and the framework established by the United Nations Framework Convention on Climate Change (UNFCCC) have paved the way for comprehensive Earth observation initiatives, and continue to accelerate public accessibility of data and information for the benefit of all. The outer space treaties have opened the skies to freedom of exploration and freedom of data generation. And in line with their UNFCCC commitment to systematic observation, states leading in space technology have made most of their climate relevant datasets available to other nations and, to a significant extent, the public.

Publicly available Earth observation information can be used to assess equitable and reasonable use. These datasets reduce the amount of information that need to be shared directly between riparian states. With the help of Earth observation technologies, water managers can base their decision-making on information that belongs to parts of the basin that lie outside of their own national boundaries. The information can also be used to enhance the lead-time for emergency notification. Additionally, the ever-increasing availability and accessibility of data generated through Earth observation technologies may change due diligence standards for riparian states (with respect to information gathering and sharing) in implementing the equitable and reasonable use principle, as well as other international water law obligations.

The monograph, published in the Brill Research Perspectives in International Water Law series, presents an exploratory assessment of the potential impacts of new data technologies on data and information exchange obligations. By highlighting the practical challenges of the use of data generated through Earth observation technologies for water management purposes, the monograph discusses how these technological innovations may, nevertheless, modify the existing contours of the rights and obligations related to data and information exchange in international water law.

New Publication Questions the Status of the UN Watercourses Convention

Thursday, January 9th, 2020

This essay is written by Gabriel Eckstein, Professor of Law at Texas A&M University, director of the TAMU Law Program in Energy, Environmental, and Natural Resources Systems, and director of the International Water Law Project. He can be reached at gabrieleckstein [at]

When the Convention on the Law of the Non-Navigational Uses of International Watercourses was adopted by the United Nations General Assembly on 21 May 1997, it was heralded as a major milestone in the evolution of international water law.  In particular, the fact that the Convention was adopted by a significant margin – 103 in favor, three against, and 27 abstentions (UNGA Press Release GA/9248) – indicated broad and robust support for what was then the only global instrument for the management of international watercourses. 

The permanent representative of Mexico to the UN at the time, Ambassador Manuel Tello, asserted that the Watercourses Convention “undoubtedly marks an important step in the progressive development and codification of international law” (U.N. GAOR, 1997, p. 2).  Even China, one of the three members who ultimately opposed the Convention, stated that they believed “the draft articles [on the law of the non-navigational uses of international watercourses] have laid a fairly good foundation for the formulation of an international convention (U.N. GAOR, 1997, p. 6).

Despite the hopes and promises of the Convention, nearly fifty years after its initial instigation at the United Nations, more than 20 years following its adoption by the UNGA, and over 5 years after it came into force (17 August 2014), enthusiasm for that instrument appears to have waned.  Although the Convention is in force for the states that have ratified it, it only attained that status following seventeen years of relatively slow progress and now has only 36 ratifying parties (Status of the Watercourses Convention).  Moreover, despite continued encouragement by various non-governmental and intergovernmental organizations, few additional states seems poised to accede to the agreement.

A new article – The Status of the UN Watercourses Convention: Does it Still Hold Water?, published in the International Journal of Water Resources Development – examines the extent of support that nations have shown the Watercourses Convention, and assess its continued sustainability.  The article does not reject the normative value of the Convention or its relevance for various nations in their efforts to engage with their neighbors over transboundary freshwater resources.  Rather, the article seeks to ascertain why relatively so few nations have ratified the instrument.

With this in mind, the article examines the support provided the Convention’s drafted norms and procedures during its development, at its historic appearance on the global stage during the 1997 vote at the UNGA, and subsequently as nations ratified the instrument and eventually brought it into force.  It also seeks to ascertain patterns in the 1997 vote and subsequent ratifications, and thereby uncover some of the possible reasons for the diminishing appeal of the instrument.  Charts and tables displaying characteristics of the votes, ratifications, riparian status, geography, and other factors are provided to support the analytical objective.

Finally, the article considers other externalities that may have negatively influenced the level of interest in the Convention that has been offered by nations.  Among others, these include divergent interpretations and misunderstanding among the international community of the norms codified in the instrument, and competition from the UNECE Convention on the Protection and Use of Transboundary Watercourses and International Lakes.

The article – The Status of the UN Watercourses Convention: Does it Still Hold Water? – is published in the International Journal of Water Resources Development and is available here.

Notification concerning Planned Measures on Shared Watercourses: Synergies between the Watercourses Convention and the World Bank Policies and Practice

Monday, June 17th, 2019

The following essay by Dr. Salman M. A. Salman is a summary of his recently published monograph (under the same title), which appears as Vol. 4(2) 2019 of Brill Research Perspectives in International Water Law.  Dr. Salman is an academic researcher and consultant on water law and policy, Editor-in-Chief of Brill Research Perspectives in International Water Law, a Fellow with the International Water Resources Association (IWRA), and the co-recipient of the IWRA Crystal Drop Award in 2017. Until 2009, he served as the World Bank Adviser on Water Law. He can be reached at: salmanmasalman [at]

Notification of co-riparian states of planned measures on shared watercourses that may result in significant adverse effects has been widely accepted as one of the established principles of international water law. This wide acceptance of notification is now codified and elaborated by the 1997 UN Watercourses Convention, which includes one separate part, with nine articles, on notification.

The duty to notify other states of activities that may affect them stems from the international obligations of good faith, good neighbourliness, and reciprocity. It is an extension of the general obligation under international law to cooperate and to exchange data and information on shared watercourses. Such cooperation is no doubt the sine qua non for the equitable, sustainable, and efficient utilization and protection of shared watercourses.

It is worth noting that the notification requirement and its components have recently become the focus of attention and developments in a number of global fora, and have energized the debate on the details of operationalizing the notification obligation. The attention covered a number of issues including the content of the notification letter, and the different types of responses thereto.

One major development in the field of notification is the decision of the International Court of Justice (ICJ) in 2010 in the Pulp Mills case. That decision has gone beyond endorsing the notification requirement under the Statute of the River Uruguay, concluded by Argentina and Uruguay in 1975. The ICJ considered notification as a sine qua non of cooperation, in addition to being a vital method for protecting the shared watercourse.

In that same year, 2010, negotiations over the Nile River Basin Cooperative Framework Agreement (CFA) among the Nile Basin countries collapsed after more than ten years of facilitation by the World Bank and some other donors. The impasse resulted from the insistence by Egypt and Sudan on the inclusion of a specific reference in the CFA to what they considered as their ‘acquired rights’ over the Nile waters (which they termed ‘water security’), as well as provisions on notification, similar to those of the UN Watercourses Convention. The CFA includes provisions on exchange of data and information, but none on notification. Because they are inter-related, these demands have been vehemently rejected by the other Nile riparians.

Another development that has highlighted the concept of notification relates to the gradual and wide acknowledgement that harm, under international water law, is actually a two-way matter with regard to the issue of quantitative allocation of the waters of shared rivers. Just as upstream riparians can harm downstream ones through storage, diversion, and use of the waters of shared rivers, downstream riparians can also harm upstream riparians by foreclosing their future uses of the shared waters through the prior use of, and the claiming of rights to such waters, and by invoking the no harm obligation. Based on this concept of foreclosure of future uses, notification has to be from all, and to all, of the riparians of the shared watercourse.

The fourth development in the realm of notification relates to the discussion and attempts of the World Bank, since 2005, to amend the provisions on notification in the Bank Policy for “Projects on International Waterways.” Indeed, the World Bank has one of the pioneering and elaborate policies, and the only practical experience, among international organizations in this field. The Policy does not establish a threshold for notification. Rather, it requires notification, as a general rule, for all projects on international waterways, and sets forth three exceptions to the notification requirement. The purpose of the proposed amendment is to align the Bank Policy with the provisions of the UN Watercourses Convention with regard to the threshold for notification.

The monograph begins with an overview of the historical and legal origins of the notification requirement. It then examines in detail the provisions of the UN Watercourses Convention as well as those of the World Bank policies dealing with notification, including the content of notification and the different types of responses that the notifying state may receive from the notified states. The monograph discusses in detail possible objections to the planed measures from riparian states, and how such objections are addressed under the provisions of the Convention and the Bank Policy and practice.

The monograph concludes by highlighting a number of comparators and synergies between the UN Watercourses Convention and the Bank Policy and practice, including the role of environmental impact assessments, shared groundwater resources, the different responses to notification, and how to handle objections from a notified state. The conclusion also stresses the potential wider positive outcomes of notification when undertaken properly and in good faith.

The full article can be accessed here.

Adapting Watercourse Agreements to Developments in International Law: The Case of the Itaipu Treaty

Tuesday, April 16th, 2019

The following essay by Dr. Maria A. Gwynn is a summary of her recently published monograph (under the same title), which appears in Vol. 4(1) 2019, of Brill Research Perspectives in International Water Law.  Dr. Maria A. Gwynn is a Senior Research Fellow at the Institute of Public International Law of the University of Bonn, and conducted most of the research contained in this monograph while she was an Oxford-Princeton Global Leaders Fellow at Princeton University and at the University of Oxford. She can be reached at maria.gwynn [at]


The UN Convention on the non-navigational uses of international watercourses recommends that states adapt their existing bilateral and regional agreements to the provisions of the Convention to promote equitable and reasonable uses of watercourses. This monograph assesses the practical consequences of this provision, and the prospects for achieving sustainable development with such action, and uses the Itaipu Treaty as a case study.

The Parana River

The Itaipu Treaty, which was signed and ratified by Brazil and Paraguay in 1973 and continues to be in force today, was established so that these two countries would jointly pursue the advantages that could be obtained from the exploitation of the Parana River to

The former Guaira Falls

produce hydropower through the construction of a dam. The Parana River is an international watercourse on the South American continent sourced by the La Plata basin. The dam was constructed at the river’s most powerful point, the Guaira Falls, formerly the greatest set of waterfalls on the South American continent, which disappeared after the construction of the dam.

The river’s great resources were not underestimated. Today, the sheer amount of energy that the Itaipu Dam produces has placed both countries among the largest producers of clean and renewable energy in the world. However, while Brazil consumes its entire share of the energy produced, Paraguay (whose available share of energy from the hydropower facilities far exceeds its own domestic energy demands) only consumes a small part of this clean and renewable energy source. Paraguay, instead, continues to use biomass sources (burning of coal and wood) to satisfy most of its energy needs. Under the Itaipu Treaty, Paraguay sells its unused allotment of energy to Brazil.In general, the Itaipu Treaty regulates the use and consumption of hydropower produced by the dam, making the provisions of the treaty very pertinent to understanding the two countries’ energy policies.

The Itaipu Dam and Reservoir

The Itaipu Treaty entered into force before the United Nations International Law Commission had finished its task of evaluating the international law and customs on the non-navigational uses of international watercourses, embodied in the UN Watercourses Convention, and before some of the major developments concerning international environmental law came about. However, the Itaipu

Treaty contains a renegotiation provision, according to which the two states must renegotiate some of its provisions 50 years following the conclusion of the treaty, i.e. in the upcoming year 2023. The monograph argues that this is a great opportunity for both countries to adapt their watercourse agreements to the current standard and principles of international law.

The monograph provides a detailed assessment of the advantages of adapting watercourse agreements to the standard and principles of all pertinent areas of international law, such as international water law, international environmental law, and climate change law. The first part of the monograph begins with an analysis of the initial approaches to the law of international watercourses in the first half of the twentieth century. It discusses some of the main principles of the law governing international watercourses and the work of pertinent institutions concerned with this area. In this sense, the first part of the monograph describes the status of the law on international watercourses at the time when the Itaipu project was first pursued.

Signing the Acta de Yguazu Agreement in 1966

The second part of the monograph discusses the Itaipu project in its legal and historical context. An analysis of the principles of consultation and notification for projects on international watercourses are particularly instructive. The monograph describes the relevance of the role of Paraguay, which despite being a main treaty party, has often been neglected in the scholarship.  The monograph shows how escalation of disputes to an international conflict regarding sovereignty was eased by benefit sharing agreements and inter-state cooperation of the countries of the La Plata basin. The monograph also offers a comparative analysis to similar cooperation and benefit sharing agreements signed at about the same time in other parts of the world.

The Itaipu Agreement

The third part of the monograph describes the advances in the law of international watercourses and of environmental law since the 1970s, and places the implementation of the Itaipu Treaty, which in turn is analyzed in the fourth part of the monograph, within this context. The fifth part of the monograph describes recent disputes concerning the non-navigational uses of international watercourses decided by the International Court of Justice in an analysis that connects the decisions of such judgments with the monograph’s object of study.

The monograph concludes by highlighting how the treaty provisions and their implementation could be affected by the developments in international law and the UN Watercourses Convention in particular. It argues that adapting watercourses agreements like the Itaipu Treaty to the provisions of the Convention is a way to foster

The UN Sustainable Development Goals

sustainable development. Doing so would be advantageous not only to the treaty parties, but also to the other countries in the water basin and to the international community as a whole.

The monograph is dedicated to the memory of Prof. Dr. Efrain Cardozo (1906-1973) and to Prof. Dr. Ruben Ramirez Pane (1920-2004).

The entire article is available here.


The International Law Association Helsinki Rules: Contribution to International Water Law

Thursday, February 7th, 2019

The following essay by Professor Slavko Bogdanović is a summary of his recently published monograph (under the same title), which appears in Vol. 3(4) 2018 of Brill Research Perspectives in International Water Law.  Professor Bogdanović was on the Law Faculty of the University Business Academy in Novi Sada in Serbia and now is a consultant on water law and policy. He can be reached at


The International Law Association (ILA) started in 1954 its study of the principles and rules of international law applicable to the rivers making or being intersected by state boundaries. It was a moment after WWII when the enhanced harnessing of hydropower potential of international rivers was seen as a necessity. The rising development needs of nations in parallel with growth of populations resulted in enlarging demand for electric energy production. Engineering aspects of harnessing rivers were not the problem; the challenge was the applicable law. The lack of accepted and pertinent international law rules was a major obstacle not only for the economic development of nations, but also to the economy of the world in general.

Early in the last century, the Geneva Convention relating to Development of Hydraulic Power affecting more than one State (1923) and other (scarce) sources of international water law had shown their limits and inadequacy not only for resolving pending developmental problems, but also for addressing serious interstate disputes concerning the rights of upstream and downstream states to the waters of international rivers (some of the more well-known disputes included the Helmand, Indus, Nile, Jordan and Yarmouk, and Columbia rivers). At the time, the U.N. International Law Commission was not willing to deal with the issue of codification of the applicable law considering it to be premature.

In the United Nations system, the problem was identified and investigated beginning in the late 1940s, and addressed continually through the 1990s when long-lasting efforts by different bodies and agencies finally resulted in the adoption of the UN Convention on the Law of Non-navigational Uses of International Watercourses in 1997.

This monograph is the result of research aimed at highlighting the details of the initial period of the ILA’s efforts to respond to the situation. Its Rivers Committee was assigned in 1954 “to study the various legal, economic and technical aspects of rights and obligations between states as to the inland waters, […] with the purpose of elaborating practical recommendations for international arrangement”. Besides a review of the broader context in which the ILA efforts and activities were situated, the monograph is focused on detailed elaboration and analysis of the documents drafted by the Rivers Committee, which, under the strong supervision and precise guidelines of the management bodies of the ILA, led step-by-step to the approval of the famous Helsinki Rules on the Uses of the Waters of International Rivers in 1966. This is followed by a discussion about the Helsinki Conference and its resolution, and then a detailed analysis of each chapter of the Helsinki Rules. The concluding part of the monograph highlights the global acceptance and wide influence exerted by the Helsinki Rules on shared water resources and related disputes, in particular the UN Watercourses Convention.

The monograph points out that the Helsinki Rules were neither ideal nor complete. As a “delicate balance between widely divergent views”, the Helsinki Rules were subject to the scrutiny of two subsequent ILA committees, which were active until 2004. Those committees studied various topics and formulated a series of articles supplementary and complementary to the Helsinki Rules with the aim of updating, upgrading and revising certain details. In that way, the Helsinki Rules served as reliable ground for further exhaustive study in this field, what eventually resulted in the comprehensive and consistent set of ILA rules compiled in the Campione Consolidation of the Rules on International Water Resources, 1996 – 1999 (2000).

The monograph also briefly indicated the attempt of the ILA to revise its entire body of international water law compiled in the Campione Consolidation, through approval of the Berlin Rules on Water Resources (2004), which diverge substantially from the key principles as set out in the Helsinki Rules and all other ILA rules subsequently approved, and from the final output of the International Law Commission on the law of non-navigational uses of international watercourses (1996), the UN Watercourses Convention (1997), and from the ICJ judgment in the Case concerning the Gabčikovo – Nagymaros Project (1997) (see Berlin Rules Dissenting Opinion).

Finally, the monograph calls for further investigation and critical analysis and evaluation of the entire body of work by the ILA in the field of international water law, including the outputs of two later ILA committees and the background leading to the approval of the Berlin Rules. The author argued that such research might show that the Helsinki Rules, in the advanced, revised and enriched form, expressed in the Campione Consolidation, are a safe pivot, marking the way out from the confusion caused by emerging proliferation of wishful concepts and ideas in this still young branch of international law.

The monograph is dedicated to the memory of Dr Dante Caponera (1921-2003), and the other members and officers of the ILA Rivers Committee.

The entire article is available here.


Shared Water Resources in West Africa – Relevance and Application of the UN Watercourses and the UNECE Water Conventions

Monday, April 16th, 2018

The following essay by Nwamaka Chigozie Odili is a summary of her recently published monograph (under the same title), which appears in Vol. 3(1) 2018, pp. 1-98, of Brill Research Perspectives in International Water Law. Mrs Nwamaka Odili is a Legal Officer with Federal Ministry of Justice, Abuja, Nigeria. She can be reached at amaka142 [at]


West Africa has twenty-five shared watercourses but only six of them are governed by legal instruments. Yet, the region, like the rest of the world, is exposed to water-related stress due to the impacts of climate change, urbanization, and overpopulation. This position results in abundance of fresh water in some countries of the region and limited or scarce availability of the resource in others. The need for a regulatory framework for managing all the region’s transboundary watercourses, therefore, cannot be overemphasized. Although the principles of customary international law apply in all cases whether there are regulatory instruments or not, treaties create obligation that are needed to strengthen the international water law system. Global framework treaties like the UN Watercourses Convention and the UNECE Water Convention provide the needed support through universal norms ‘to shape the content of instruments adopted at the regional and basin level’ (Laurence Boisson de Chazournes, ‘Freshwater and International Law: the Interplay between Universal, Regional and Basin Perspectives’ (Paris, UNESCO, 2009) at 5).

Transboundary Watercourses in West Africa



Transboundary WatercourseRiparian States
Niger River BasinNigeria, Niger, Burkina Faso, Côte d’Ivoire, Benin, Cameroun, Guinea, Mali, Chad
Lake Chad BasinCameroun, Nigeria, Chad, Central African Republic, Niger, Libya
Volta River BasinGhana, Burkina Faso, Benin, Togo, Côte d’Ivoire and Mali
Senegal River BasinSenegal, Guinea, Mali, Mauritania
Gambia River BasinGambia, Guinea, Guinea Bissau, Senegal
Koliba-Korubal River BasinGuinea and Guinea Bissau



Transboundary WatercourseRiparian States
Cross River BasinNigeria and Cameroon
Akpa Yafi River BasinNigeria and Cameroon
Queme River Basin Nigeria and Benin
Tano River BasinGhana and Côte d’Ivoire
Komoe River BasinCôte d’Ivoire, Ghana and Burkina Faso
Atui River BasinMauritania and West Sahara
Mono River Basin Togo and Benin
Bia River BasinGhana and Côte d’Ivoire
Sassandra River BasinGuinea and Côte d’Ivoire
Cavally River BasinCôte d’Ivoire, Guinea and Liberia
Cestos River BasinCôte d’Ivoire, Guinea and Liberia
St John River BasinLiberia and Guinea
St. Paul River BasinLiberia and Guinea
Loffa River BasinLiberia and Guinea
Mana Morro River BasinLiberia and Sierra Leone
Moa River BasinLiberia, Sierra Leone and Guinea
Little Scarcies River BasinSierra Leone and Guinea
Great Scarcies River BasinSierra Leone and Guinea
Geba River BasinGuinea Bissau, Guinea and Senegal

Since adoption of the General Act of Berlin in 1885, which dealt, inter alia, with the Niger River, more agreements have been contracted for the management of some of the shared watercourses in West Africa, particularly in the post-colonial era. Hence, West Africa contributed through these agreements to the development of international water law prior to the adoption of the UN Watercourses Convention and the UNECE Water Conventions in the 1990s. Initial instruments dealt primarily with navigation, while later agreements addressed the need for co-operation and incorporated other principles of customary international water law. The two conventions, no doubt, have influenced this trend such that water regimes in the region improved over time. This raises the question: do riparian states in West Africa need to be parties to either or both water conventions to enhance management, sharing and protection of their shared watercourses?

The influence of the UN Watercourses Convention in the region is established because water regimes implemented after adoption of the UN Watercourses Convention reflect some of its substantive and procedural provisions. Moreover some countries in West Africa are parties to the Convention. On the other hand, influence of the UNECE Water Convention in the region is limited and its potential benefits have yet to be determined. Article 25 and 26 of the UNECE Water Convention were amended to allow non-UNECE states that are members of the United Nations to become parties to the Convention. However, its mandatory provisions regarding basin organization and compliance with its stringent requirements, details, and tasks necessitates significant foreseeable financial and technical resources, which countries in West Africa now lack.

Although most West Africa water instruments are flawed by loopholes and there is need to address the problems generated by unregulated shared watercourses in the region, West Africa nations do not need to be contracting parties to both the UN Watercourses Convention and the UNECE Water Convention. What West Africa needs is a treaty position that accommodates the reality of the management of its transboundary water resources. Adoption of global treaties by the states of West Africa is not sufficient because the universal law in those treaties needs to be complemented by regional or basin agreement for realistic implementation. The important issue is not which global convention the states belong to, but rather how strong and efficient transboundary water resources management in the region has grown over time. To achieve this goal and to further address major gaps and failings in transboundary water resources management in West Africa, states in the region could negotiate a region-based water treaty to reflect the needs and concerns of the region and supplement it with basin-specific treaties.

The entire article is available here.


Inter-State Water Law in the United States of America: What Lessons for International Water Law?

Monday, September 25th, 2017

The following essay by Professor Rhett Larson is a summary of his recently published monograph (under the same title), which appears in Vol. 2.3, 2017, pp. 1-82, of Brill Research Perspectives in International Water Law. Professor Larson is a Professor of Law at the Arizona State University School of Law. He can be reached at Rhett.Larson [at]


John Wesley Powell was an 19th Century explorer of the western United States. In a report to the U.S. Congress, Powell recommended that the borders of future western states be based on watersheds and warned of the risks associated with political subdivisions sharing transboundary waters. Congress ignored Powell’s advice, and established western state boundaries with many inter-state waters traversing and, in some cases forming, sub-national borders. As a result, and as I discuss in my recent monograph published in Brill Research Perspectives on International Water Law, the United States has a long and colorful history of transboundary water management that provides both encouraging lessons and cautionary tales for international water law.

For example, the common law doctrine of “equitable apportionment” developed by the U.S. Supreme Court in cases involving its original jurisdiction over inter-state water disputes is similar in many respects to the principle of equitable and reasonable utilization embodied in Articles 5 and 6 of the U.N. Convention on the Law of the Non-Navigational Uses of International Watercourses ( “Watercourse Convention”).

RhettLarson-Inter-State_Water_Law_in_the_USBeyond the obvious use of the word “equitable” in the articulation of both the inter-state doctrine and the international doctrine, the factors set forth by the U.S. Supreme Court in determining equitable apportionment are similar to the factors laid out in Article 6 of the Watercourse Convention in determining equitable utilization. The U.S. Supreme Court considers “physical and climatic conditions,” and international law considers “[g]eographic, hydrographic, hydrological, climatic, ecological and other factors of a natural character.” The U.S. Supreme Court considers consumptive uses, while the Watercourse Convention includes considerations of the “effects of the use or uses of watercourses.” The U.S. Supreme Court considers wasteful uses, and the Watercourse Convention includes considerations of conservation options.

Despite these similarities, the U.S. doctrine of equitable apportionment and the factors included in determining reasonable and equitable utilization under the Watercourse Convention have differences that are important to note for what each doctrine may learn from the other. The Watercourse Convention expressly includes consideration of population, which seems an obvious factor missing from inter-state water law. The Watercourse Convention also considers both existing and potential uses of the watercourse, while the U.S. doctrine of equitable apportionment considers only “consumptive uses,” not necessarily potential future uses. It might also be helpful for the U.S. doctrine of equitable apportionment to expressly factor in ecological considerations in a way similar to the Watercourse Convention, because those considerations may not always be adequately captured by the concept of waste embodied in the U.S. law.

On the other hand, the U.S. equitable apportionment doctrine includes a cost-benefit analysis consideration that could be a helpful factor to evaluate equitable utilization in international water law. Additionally, the consideration of the character and rate of return flows under U.S. inter-state water law may also be a helpful factor to include in determining equitable utilization in international water law.

In Bean v. Morris, an early equitable apportionment case before the U.S. Supreme Court, the Court identified an important factor when evaluating inter-state water allocations that could be incorporated into international equitable and reasonable utilization analysis. States in the U.S. typically rely on one of two legal regimes for allocation rights to water. The approach to water rights in eastern states is generally common law riparian rights based on English and Roman laws, under which rights are apportioned to owners of property abutting water bodies based on the requirement that uses be reasonable. The approach to water rights in western states is generally prior appropriation, with water rights based on a first-in-time, first-in-right scheme, subject to beneficial use requirements and the prohibition against waste.

Neighboring U.S. states sharing transboundary waters can therefore have dramatically different approaches to allocating water rights and different policy aims in water management. These differences have aggravated inter-state water disputes over transboundary waters. The U.S. Supreme Court, in an early equitable apportionment case, sought to mitigate the impact of, if not reconcile, these different approaches to water rights. In Bean v. Morris, the Supreme Court held that it would apply principles of prior appropriation when allocating water between states that recognize prior appropriation as their own internal water rights system.

International water law could similarly look to using domestic water law principles held in common between two nations sharing a watercourse as a factor in the evaluation of reasonable and equitable utilization. Such an approach would be a more targeted application of Article 38(1)(c) of the International Court of Justice’s statute authorizing reliance on “general principles of law recognized by civilized nations” in resolving international disputes. Nations are perhaps more likely to view such a factor as reasonable and equitable if based on domestic laws already accepted and legitimized under their respective domestic laws.

Other potentially helpful lessons from U.S. inter-state water law for international water law may include the use of special masters to facilitate dispute resolution and the recognition and quantification of water rights held by indigenous peoples. Cautionary tales for international water law from U.S. inter-state water law include the inter-state problems created by the bifurcation of groundwater and surface water rights, and the over- or under-empowerment of basin-level, inter-jurisdictional commissions. Many countries with federal structures, like the United States, have been dealing with inter-jurisdictional water disputes for generations, and therefore could be fertile ground for cultivating ideas for reform in international water law.

The entire article is available here.

New Book Explores the International Law of Transboundary Groundwater Resources

Sunday, September 17th, 2017

The following essay by Gabriel Eckstein provides an overview of his forthcoming book on The International Law of Transboundary Groundwater Resources. The book should be released on 20 September 2017.

Approximately 600 aquifers worldwide traverse international frontiers. Yet, only four of these have been the direct focus of a treaty regime. In sharp contrast, more than 3,600 treaties have been crafted for the 276 shared rivers and lakes of the world. As a result, the international law applicable to transboundary groundwater resources is far less developed and understood than its surface water counterpart. To a significant extent, international groundwater law has yet to emerge on the international stage.


TBA Map - colour


Nevertheless, increased regional scarcities and growing demand for freshwater resources have forced many governments to focus on all of their freshwater resources, including those found below the surface along their borders. In places like the Middle East, North and sub-Saharan Africa, parts of Central Asia, and the Mexico-United States border, nations have come to realize that transboundary aquifers serve as the primary or sole source of freshwater for their communities and natural environment.

As a result, various countries and international organizations are now beginning to explore legal options for the management of these subsurface water bodies.  Both the UN International Law Commission and the UN Economic Commission for Europe have issued proposed norms aimed at guiding transboundary aquifer riparians on how to develop such regimes (see UN Draft Articles on the Law of Transboundary Aquifers, and UNECE Model Provisions on Transboundary Groundwaters). And agencies like the UN Educational, Scientific, and Cultural Organization are developing case studies and evaluating management approaches with the goal of developing equitable cooperative regimes.

While the international law applicable to transboundary groundwater resources is still in its infancy, progress is evident and preliminary trends can be discerned.  This books documents these developments and offers a fairly comprehensive look at the evolutionary process that has led to the emergence of what may yet be termed international groundwater law.

IGWLBookCoverThe book opens with a general overview of the importance of groundwater resources to communities and humanity on a global scale. It then placed groundwater in a transboundary context and recognizes the governance challenges that arise among aquifer riparians. Taking a decisively interdisciplinary approach, Chapter 2 discusses groundwater resources in accessible scientific terms and lays the foundations for applying scientifically sound laws and policies to transboundary groundwater resources. It considers groundwater within the broader hydrologic cycle and describes and defines the various hydrogeological concepts and processes that must be considered by groundwater managers and regulators.  The book then discusses in Chapter 3 groundwater in a cross-border context and presents six conceptual aquifer models to illustrate various scenarios in which groundwater resources can have transboundary implications.  The models are all scientifically valid generic models, and are based on and represent the vast majority of circumstances found in nature under which an aquifer may have transboundary implications.

In Chapter 4, the book turns to the law and explores how groundwater has been treated in various domestic legal regimes and traditions, as well as in formal and informal arrangements between aquifer riparian states. This discussion lays the foundation for the growing attention paid to transboundary aquifers among governmental, inter-governmental, and non-governmental entities, and their interest in identifying globally acceptable legal norms and rules for managing groundwater resources that traverse international boundaries.  Chapter 5 follows with an analysis of groundwater resources and aquifers under the U.N. Watercourses Convention, while Chapter 6 focuses on groundwater and aquifers under the UN Draft Articles on the Law of Transboundary Aquifers.

Taking into account the preceding chapters, Chapter 7 discusses the emerging trends in the evolution of international law for transboundary aquifers. It begins by reviewing the few formal and informal arrangements in existence in which nations have addressed directly the management or use of a transboundary aquifer. It then extracts those principles and norms that are common to all or most of these instruments and evaluates them as a basis for the possible emergence of international law. The book concludes with Chapter 8 where it identifies gaps in the law in light of the unique characteristics (especially as compared to surface water bodies) of groundwater resources and their potential cross-border implications. This final chapter is intended as a basis for further discussion and consideration of the continued development of this nascent but critical area of international law.

For more information about this book, please see here.  To request a review copy, see here; Instructors can request an e-book exam copy here.


Disputes over International Watercourses: Can River Basin Organizations make a Difference?

Friday, July 21st, 2017

The following essay by Sabine Blumstein and Susanne Schmeier is a summary of a recently published book chapter titled “Disputes Over International Watercourses: Can River Basin Organizations make a Difference?”. Ms. Blumstein works as a Project Manager at adelphi. Ms. Schmeier is Coordinator for Transboundary Water Management at the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ). They can be contacted at: blumstein[at]


Book coverDisagreements or even full-fledged disputes over the use of water resources in shared basins have increasingly made headlines in the past years. Developments in the Mekong, Nile, Syr Darya, Indus and other basins have led more and more scholars, as well as policy-makers and journalists, to warn of the risk of water conflicts or even wars. This revives – albeit in a more informed manner – the water wars debate of the early 1990s. While much progress has been made since then – especially through the creation and institutionalization of cooperative arrangements in many shared basins – disputes nonetheless continue to occur. And they do occur even in basins with River Basin Organizations (RBOs) in place, which have often been set up to solve, mitigate or prevent such disputes.

However, research on transboundary river basin management as well as empirical evidence from basins around the world suggest that RBOs do make a difference. They provide a variety of direct and indirect mechanisms for dispute resolution, as discussed in a recently published chapter which appeared in “Management of Transboundary Water Resources under Scarcity. A Multidisciplinary Approach”. In this chapter, the authors shed light on how RBOs engage in the solution of disputes that arise over water resources in transboundary basins. And they show that it is not dispute-resolution mechanisms in the narrow sense – often identified as the key if not the only instruments RBOs provide – that make a difference in whether a conflict is solved peacefully in a cooperative manner. Instead, it is the broader cooperative framework of RBOs that matters.

The authors review existing dispute resolution mechanisms of international RBOs around the world in a comprehensive manner. Their research indicates that more than 50% of the 121 analyzed RBOs have a dispute resolution mechanism in place – seemingly a good starting point. Among those, they identify three broader categories of RBO dispute resolution mechanisms: bilateral negotiations between those RBO members involved in a disagreement; RBO-internal mechanisms; and external actors’ involvement. Often, states have opted to establish more than one step in the respective dispute-resolution mechanism, structuring the processes in two instances with different mechanisms to be applied. For instance, bilateral negotiation between disputing parties (facilitated by the RBO) are often followed by a possible engagement of external actors – both 3rd party mediators and judicial ones.

The authors also provide explanations for why dispute resolution mechanisms vary around the world (in terms of existence in the first place, but also in design). Often, it is the history of cooperation (also beyond the water sector) that determines both the existence as well as the exact design of dispute resolution mechanisms. The high share of dispute resolution mechanisms in African RBOs, for example, can be explained by the past conflicts found in many African basins as well as the high presence of international donors, which often consider well-defined dispute-resolution mechanisms as a prerequisite for successful cooperation. In Europe, on the other hand, the existence of cooperation mechanisms (including specific instruments for solving disputes) in many issue-areas has limited the need for well-defined dispute resolution mechanisms within specific basins and RBOs.

Regional distribution of dispute-resolution mechanisms in RBOs

    Regional distribution of dispute-resolution mechanisms in RBOs

In the second part of the chapter, the authors analyze two conflicts in greater detail in order to shed more light on how exactly RBOs make a difference in solving or mitigating disputes in shared basins. For the Mekong River Basin, they find that while the Mekong River Commission’s (MRC) dispute resolution mechanisms themselves (see Art. 34 and 35 of the 1995 Mekong Agreement) might seem insufficient for addressing issues as complex as recent hydropower developments and related inter-state conflicts, the MRC provides ample other tools for ensuring that such disputes get addressed in a cooperative manner and on the basis of comprehensive technical data and information. Although having been criticized by many scholars, the MRC’s Procedures for Notification, Prior Consultation and Agreement (PNPCA) and the processes established around them (e.g. the identification of environmental and socioeconomic baselines, the establishment of guidelines for impact mitigation, etc.) have ensured that disagreements have been handled in a rather cooperative manner. This is particularly obvious if compared to similar situations of unilateral hydropower development in other basins around the world.

For the Nile River Basin, the authors find that the Nile Basin Initiative (NBI) did not directly contribute to diplomatic negotiations or any other form of direct resolution of the conflict around the Grand Ethiopian Renaissance Dam (GERD), which can partly be explained by the absence of any NBI dispute resolution mechanism. In addition, the lack of any notification mechanism or requirement to exchange data/information on planned infrastructure measures which could potentially impact downstream countries, prevented the NBI to play any significant role in averting the dispute in the first place. Despite this limited role in conflict prevention and direct diplomatic engagement, NBI played an important role in defusing the conflict through broader activities around data and information sharing and increasingly distributing this knowledge to the broader public. The RBO’s activities regarding knowledge distribution and more neutral reporting through national media is an important contribution to de-securitize national discourses around the construction of GERD and hence a precondition for any final resolution of the dispute.

While the findings reveal that the existence of specific dispute resolution mechanisms in a narrow sense does not necessarily influence the success of dispute resolution and depends on a number of other intervening factors, RBOs as a whole do matter in 2addressing water-related conflicts. This is because RBOs provide a range of instruments beyond pure dispute resolution mechanisms: amongst others, they provide platforms for negotiation and exchange, data and information exchange or notification procedures. These instruments are of key importance to solve, contain or even prevent conflicts. Water practitioners and policy actors should therefore not exclusively focus on the specific dispute resolution mechanisms provided by RBOs but be aware of and actively use the broader repertoire of governance instruments provided by RBOs to avoid and solve evolving disputes in transboundary river basins.