Abstract
Introduction
Transboundary water law has traditionally focused on water allocation, scarcity, and pollution, while the governance of transboundary flood risks associated with upstream water infrastructure has received comparatively limited legal attention. This article examines how international water law addresses upstream state due diligence and transboundary flood risk through the case of the Shabelle and Juba River basins shared by Ethiopia and Somalia.
Methods
The study employs a qualitative doctrinal legal methodology combined with governance-oriented case study analysis to examine the principles of equitable and reasonable utilization, the obligation not to cause significant harm, due diligence, and sustainable development. The article does not seek to attribute particular historical flood events in Somalia to specific upstream dam releases. Rather, it examines the legal obligations applicable where upstream water infrastructure, climatic variability, hydrological uncertainty, and downstream vulnerability interact to create or modify foreseeable transboundary flood risks.
Results
The historical flood events considered in the case study are used to illustrate recurrent downstream flood exposure and vulnerability, while the available evidence does not establish that particular events were caused or intensified by specific upstream dam operations. Establishing such attribution would require sufficiently detailed and temporally matched information concerning reservoir operations, release volumes and timing, upstream and downstream discharge records, rainfall conditions, and other hydrological factors, which is beyond the evidentiary basis of this study. The article therefore advances a risk-based due-diligence framework for assessing compliance with applicable preventive and procedural obligations, emphasizing foreseeability, environmental assessment, prior notification, consultation, hydrological information exchange, early warning, and adaptive operational management. The Shabelle and Juba basins demonstrate how weak institutional coordination, limited information exchange, and the absence of effective joint governance mechanisms can increase downstream vulnerability in fragile and climate-sensitive contexts.
Discussion
The article contributes to international water law scholarship by reframing transboundary flooding as a distinct field of legal inquiry and demonstrating how greater attention to preventive and procedural obligations can strengthen accountability and cooperative flood-risk governance under conditions of uncertainty.