Unauthorized groundwater use: institutional, social and ethical considerations Lucia De Stefano* and Elena Lopez-Gunn Water Observatory, Botín Foundation, Departamento de Geodinámica, Facultad de Ciencias Geológicas, Ciudad Universitaria, Universidad Complutense de Madrid, 28040 Madrid, Spain *Corresponding author. E-mail: luciads@geo.ucm.es Abstract In many areas of the world, particularly in arid regions or in areas experiencing population growth, there is increased competition over scarce water resources. This is likely to increase in the future due to continued popu- lation growth, urban expansion and the challenge of the impact of climate change on water resource availability. In this context, groundwater is likely to play a pivotal role in facing water scarcity. When different users share a common-pool resource, basic rules are usually established to manage access to the resource and ensure balance between demand and supply. Water authorities worldwide are increasingly paying added attention towards regulat- ing the use of groundwater because of its strategic value, e.g. in times of drought or as a natural reserve. In the case of groundwater, although regulatory measures exist, they are often difficult to enforce. This paper explores the situation with a discussion of two aspects: first (and in line with this special issue on water ethics), an examination of the fundamental individual values that underpin behavior in relation to water use, and second, an investigation of the typologies of unauthorized water use, its main potential impacts, potential root causes and reflections on imperfect institutions and social norms. Keywords: Groundwater; Illegal use; Regulation; Spain 1. Introduction In many areas of the world, and particularly in arid regions, there is increased competition over scarce water resources. This is likely to increase in the future due to continued population growth, an increase in living standards, urban expansion and the challenge of the impact of climate change on water resource availability. In this context, groundwater is likely to play a pivotal role in facing water scarcity due to its still partially unexploited potential and its intrinsic resilience to rainfall variability. Over the last decades, groundwater use has experienced a spectacular increase over the entire world, enabling the development of formerly depressed areas. This ‘silent revolution’ was led by millions of Water Policy 14 (2012) 147–160 doi: 10.2166/wp.2012.101 © IWA Publishing & the Botín Foundation 2012 Downloaded from https://iwaponline.com/wp/article-pdf/14/S1/147/406174/147.pdf by guest on 20 May 2020