The international legal architecture to manage freshwater and ocean ecosystems does not adequately provide for the interconnected nature of these ecosystems or the transboundary harm flowing between them. Pollution from land-based sources exemplifies this issue where plastic, agricultural run-off, discharge of nutrients and pesticides and untreated sewage accounts for approximately 80% of all marine pollution globally and is not adequately addressed by international law. This paper examines the following question: What role have international freshwater and marine regimes and courts played in clarifying the normative content of the due diligence rule to avoid significant transboundary environmental harm, including harm from land-based sources of pollution? The discussion demonstrates that although international regimes have made a substantial contribution to clarifying the no-harm rule, significant gaps remain. For example, the need for further guidance regarding the obligation to take ‘all appropriate measures’ to avoid transboundary harm or the previous absence of due diligence standards to prevent marine pollution from land-based sources. This paper demonstrates how courts have contributed to a coherent interpretation of the no-harm rule across international freshwater and oceans law. It pinpoints instances where courts have taken a progressive approach, taking account of the latest developments in technology, assessing an acceptable level of risk, considering the interconnected ecosystem impacts of developments and quantifying compensation for environmental harm and also identifies examples where courts have not gone far enough. Finally, this paper discusses how regional seas regimes and recent global soft law developments have taken progressive steps towards addressing harm from land-based sources of pollution.

中文翻译：

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国际制度和法院在澄清淡水和海洋环境保护中的损害预防方面的作用

管理淡水和海洋生态系统的国际法律架构没有充分规定这些生态系统的相互关联性或它们之间流动的跨界损害。陆源污染就是这个问题的例证，其中塑料、农业径流、营养物质和杀虫剂的排放以及未经处理的污水约占全球所有海洋污染的 80%，国际法没有充分解决。本文研究了以下问题：国际淡水和海洋制度和法院在澄清尽职调查规则的规范内容以避免重大跨界环境损害方面发挥了什么作用，包括陆源污染造成的危害？讨论表明，尽管国际制度为澄清无害规则做出了重大贡献，但仍然存在重大差距。例如，需要就采取“一切适当措施”避免跨界损害的义务提供进一步指导，或者之前缺乏防止陆源海洋污染的尽职调查标准。本文展示了法院如何促进对国际淡水和海洋法中无伤害规则的一致解释。它指出了法院采取渐进式方法、考虑到技术的最新发展、评估可接受的风险水平、考虑发展的相互关联的生态系统影响并量化对环境损害的补偿，并确定法院做得不够的例子。最后，本文讨论了区域海洋制度和最近的全球软法发展如何采取渐进步骤来解决陆源污染造成的危害。