Tradeoffs between Water Uses and Environmental Flows: A Hydroeconomic Analysis in the Ebro Basin

Daniel Crespo,Safa Baccour,Jose Albiac,Encarna Esteban,Taher Kahil

doi:10.1007/s11269-019-02254-3

Abstract

Environmental water uses and their social values have been mostly overlooked in traditional water management over the last few decades, and recently, the maintenance of environmental flows has been considered a key issue in water policies. Addressing the more sustainable management of water resources involves introducing new water allocation policies. However, these policies are often associated with tradeoffs across sectors, stakeholders, and spatial locations. This study aims to evaluate the tradeoffs and political economy aspects of allocating water among economic water uses and environmental flows in water-scarce river basins. An empirical analysis has been conducted in the Ebro River basin (Spain) as a case study, where an intense debate on the environmental flow allocation of the Ebro mouth is taking place. The study uses a hydroeconomic model that includes the major water uses in the Ebro to analyze the effects of different water allocation policies under combinations of water availability and environmental flow scenarios. The results of this study highlight the importance of assessing the opportunity costs and political implications of reallocating water from economic activities to the environment under impending climate change impacts. Moreover, the results indicate that well-functioning water allocation policies should be not only economically efficient but also socially acceptable to reduce the likelihood of failure of water reallocation to the environment.

Highlights

Global water extractions have become increasing rapidly in recent decades to sustain a larger population and more prosperous economies (Biemans et al 2011; Liu et al 2017)
The proportional sharing policy distributes water shortages evenly among all irrigation districts in the basin, and the costs of drought are between 150 and 190 million Euros per year. These results suggest that the current water allocation regime in the Ebro basin is able to balance economic activities with the environmental flow requirements of ecosystems, and this balance is maintained under different levels of water availability
The emerging social demands for environmental protection in the form of secured minimum environmental flows for water-dependent ecosystems and climate change impacts will further increase the competition for already scarce water resources in many basins worldwide

Summary

Introduction

Global water extractions have become increasing rapidly in recent decades to sustain a larger population and more prosperous economies (Biemans et al 2011; Liu et al 2017). This growing pressure on water resources has created widespread water scarcity problems in many basins around the world, indicating that water mismanagement is quite common. Policies implemented to address water scarcity in water-stressed basins frequently fail because of the lack of accurate assessments of the economic and environmental tradeoffs associated with water allocation decisions. An example is the case of Europe, where water legislation emphasizes the objective of maintaining a good ecological status for all water bodies

Objectives

Results

Discussion

Conclusion