International water conventions—e.g., the 1997 United Nations Convention on the Non-Navigational Uses of International Watercourses—include positive but insufficient focus on groundwater and its interaction with surface water. As such, a growing body of literature has proposed modifications to existing frameworks to enable consideration to surface and groundwater and their interactions. While this literature places considerable focus on coupling and amending existing legal frameworks, elaboration and evaluation of a new protocol on conjunctive water management comprises a key gap. To fill this gap, this paper seeks to answer the following question: does formulation and adoption of a new “conjunctive” protocol provide more value than existing proposals centered around modifications to existing law? This paper seeks to compare benefits associated with current proposals to strengthen the international legal framework for management of surface–groundwater interaction, vis-a-vis adoption of a new protocol on conjunctive management of transboundary freshwaters. To do so, the authors use doctrinal legal methods to analyze the existing main instruments globally assessing the degree to which they consider key interlinkages between surface water and groundwater. Then, the paper examines the concept of conjunctive water management and deduces tenets that should be pursued in shared waters to achieve this objective. To identify the preferred option to support conjunctive water management in international water law, the paper explores the degree to which existing proposals vs a new protocol enable an embrace of these tenets of conjunctive water management. The paper finds that while a new protocol may add greater value in advancing conjunctive water management, multiple options can and should be concurrently pursued. In particular, the authors argue that new protocols to the existing treaties must be adopted in combination with the amendment of the Draft Articles on the Law of Transboundary Aquifers. Benefits of doing so include more effective management of transboundary freshwater resources that are interconnected hydrologically, a less fragmented and more consistent international water regime, and ultimately more benefits accruing to the populations and environmental goods dependent on shared water resources.

国际水资源公约——例如1997 年联合国国际水道非航行使用公约——积极但不够充分地关注地下水及其与地表水的相互作用。因此，越来越多的文献提议对现有框架进行修改，以考虑地表水和地下水及其相互作用。虽然这些文献相当重视结合和修改现有的法律框架，但对联合水资源管理新协议的阐述和评估构成了一个关键差距。为了填补这一空白，本文试图回答以下问题：制定和采用新的“联合”协议是否比以修改为中心的现有提案提供更多价值？现行法律？本文旨在比较当前加强地表水-地下水相互作用管理国际法律框架的提议与采用跨界淡水联合管理新议定书的好处。为此，作者使用理论法律方法分析全球现有的主要文书，评估他们考虑地表水和地下水之间关键相互联系的程度。然后，本文研究了联合水资源管理的概念，并推导出为实现这一目标而在共享水域中应遵循的原则。为了确定在国际水法中支持联合水资源管理的首选方案，本文探讨了现有提案与一项新的协议使这些联合水资源管理的原则得以接受。该论文发现，虽然新协议可能会在推进联合水资源管理方面增加更大的价值，但可以而且应该同时采用多种选择。特别是，作者认为，必须结合对跨界含水层法条款草案的修正案，通过现有条约的新议定书。这样做的好处包括更有效地管理在水文方面相互关联的跨界淡水资源，一个不那么分散和更加一致的国际水资源制度，以及最终为依赖共享水资源的人口和环境产品带来更多利益。