Chapter 3 - Environmental flows as a component of Integrated Water Resources Management: Historical-political developments and the long way to successful implementation

Abstract

Approximately 60,000 large dams and 800,000 smaller ones are operating worldwide to generate electricity, prevent flooding, and supply water for domestic, agricultural, or industrial uses. At the same time, these dams block ecological processes in, constantly increasing, 63% of the world’s large rivers, and thus their societal benefits have been often counterbalanced by their ecological/societal consequences. Upon this realization, the notion of integrated water resources management (IWRM) was conceptualized at the United Nations (UN) Conference on Water (1977) and was further developed at the International Conference on Water and the Environment (1992) and the UN Conference on Environment and Development (1992). Most UN members have hence committed to implement IWRM plans toward the sustainable management of their freshwater resources. The IWRM principles were soon afterward incorporated into global action agendas (Agenda 21, Brazil 1992; Millennium Development Goals, Brazil 2012; Agenda 2030, USA 2015). The concept of environmental flows was independently developed since the late 1940s, and was ultimately incorporated into IWRM after the International River Symposium and Environmental Flows Conference (2007), as a fundamental tool for the implementation of national IWRM-focused strategies. Yet, in 2019, only 38% of the UN members had established appropriate legal frameworks to facilitate the practical implementation of environmental flows. Currently only 14% of the world’s longest rivers are hydrologically protected by regularly receiving environmental flows. Through a review of (1) the historical–political developments in environmental flows management, (2) the environmental water laws of each country, and (3) the actual environmental flows implementation status of the world’s longest rivers, many of which flow unprotected through mountainous landscapes, this chapter provides a detailed historical–political overview and identifies the gap between theory and practice in environmental flows determination and allocation.