ABSTRACT
River basins or sub-basins are said to be ‘closed’ when their water supply is insuffi cient to meet consumptive demands and environmental needs (Molle et al. 2010). As demographic, economic and social pressures on water bring more and more basins near closure, the use and transfer of water between and within sectors have become subjects of increasing public attention. At a global scale, about 1.2 billion people live in closed basins, and another 500 million live in basins approaching closure (De Fraiture and Perry 2007).
There is an increasing literature on basin closure (Molle 2004; Falkenmark and Molden 2008; Venot et al. 2007; Smakhtin 2008; Molle 2008; Molle et al. 2010), but most studies are conceptual and descriptive, focusing on the current situation rather than providing a comprehensive picture of ‘how we got here’. The objective of this chapter is to provide a detailed picture of the some of the trajectories that led to the closure of the Guadalquivir River Basin of southern Spain. This river basin (RB) represents a typical waterscarce situation in the Mediterranean, with increasing demand for water resources, especially for irrigation, the main water user. To better understand how the Guadalquivir RB reached closure, we discuss its development using a Driving force-Pressure-State-Impact-Response (DPSIR) framework, applying data from the ‘Irrigation Inventory of the Guadalquivir RB’ for 2008 (CHG 2010a). We focus on irrigated agriculture because agriculture consumes more than 85% of all water extracted from the RB and it also has the biggest potential for water savings. Furthermore, regions suffering from water scarcity (and the possibility of closure) tend to coincide with regions in which irrigation is a major water user (Berbel et al. 2007).
