Collective management of irrigation in eastern Spain. Integration of new technologies and water resources.

Abstract

The aim of this thesis is to analyze how farmer-managed systems adapt to the changes related to the integration of new water resources and drip irrigation technologies. Chapters two and three study the operating principles for water management. These principles, when applied by farmers as collective rules, result in interactions that create equity on water rights and transparency. The study area includes the irrigation system of the Huerta of Valencia (Spain). This system, well known internationally, has traditionally used surface water from the Turia River. Though recently, the use of groundwater and treated wastewater have been integrated with surface water. In this context, the analysis evolves around the subject of how the rules, developed for the sharing of surface water, have been adapted for conjunctive use of these new water resources. In addition, attention is also placed on how this process was crucial for the management of the 2005 - 2008 drought period. Results show that the operating principles, based in the proportionality and uniformity on irrigation frequency between users, underlie a system of distribution that is equitable, transparent and robust. In addition, the use of drought emergency wells and the reuse of treated wastewater have not resulted in any important conflict. These resources are used together with surface water during drought periods, increasing the guarantee of supply. However, treated wastewater use affects the uniformity on irrigation frequency among Water User Associations. Besides, Groundwater User Associations overlap in irrigated surface, farmers and infrastructure with Water User Associations using surface water. This situation results in informal conjunctive, a strategy that seems effective to deal with drought. Chapter four analyses the conversion to drip irrigation, an important technological transformation. In order to do that, institutional and management changes are examined. The cases studied are the Acequia Real del Jucar, the Jucar-Turia Channel and the General Community of Irrigators of Vall d'Uixo. At Water User Association level a centralization of managment has been observed (in the irrigation network, water resources managment and the merging of preexisting associations). In addition, the reasons to convert, the advantages, disadvantages and the satisfaction of users are also assessed. Besides, the work examines some aspects of how users adapt the use of irrigation and fertigation technology to their needs, diverging in some cases from the initial criteria of design. Chapter five discusses and compares the implications of the previous chapters. Some aspects of irrigation management and governance are assessed in a more detailed manner for the case of gravity irrigation Water Users Associations. In addition, the changes related to the introduction of drip irrigation technologies and new water resources are further compared In conclusion, the thesis reflects on current water policy dilemmas, focusing in currently prevailing water policy measures in the Valencia region, but also at world level: drip irrigation implementation, reuse of treated water and conjunctive use of groundwater and surface water. This allows identifying and comparing local aspects that influence the adoption and adaptation of new technologies and the integration of new water sources. Considering these features in irrigation policy would increase the efficacy of traditional solutions. Including these perspectives would also help to adapt new solutions to collective water and irrigation management settings characterized by significant complexity.