The issues of wastewater treatment and the reuse of water are of great importance, especially in areas where the shortage of conventional resources is a structural problem, as it is in the case of Spain. Wastewater reuse is a valid mechanism to avoid problems derived from droughts and water scarcity. It allows access to water resources in areas with water restrictions and to prevent futures scenarios, due to it being expected that water consumption will double by 2050 over the world. Thus, the likelihood that this unconventional, strategic resource would become scarce is unquestionable, particularly in cases where water planning and exploitation systems prioritize the preservation, protection, and improvement of water quality, as well as the sustainable and efficient use of natural resources. This paper shows how wastewater treatment and reuse are linked, as the reuse of wastewater is associated with a previous regeneration, and both of them are essential tools for maximizing environmental outcomes, as called for in the European Union Directives.

In the context of climate change, a significant increase in the flood risk is expected, which may lead to an intensification of the social impacts of disasters. Social impacts significantly affect the recovery processes of individuals, social groups, and institutions in the medium and long term. Hence, the management of such impacts throughout the disaster life cycle is essential. International institutions and frameworks for disaster risk reduction have claimed the need to generate tools for the systematic assessment and management of social impacts of floods. Recently, an innovative line of research has emerged aimed at adapting social impact assessment (SIA), usually directed at the evaluation of planned interventions (programs, plans and projects), to the field of environmental disasters. In order to contribute to academic efforts in this emerging field, this paper puts forward, through a systematic literature review based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria, an SIA methodological proposal for the identification, assessment and systematic management of the social impacts of flood events. This methodological proposal covers the three phases of the disaster cycle: (1) pre-event (preparedness), allowing the anticipation of potential impacts and supporting the proposal of preventive measures; (2) event (response), facilitating a strategic mobilization of resources and technical support towards previously identified critical disaster areas; and (3) post-event (recovery), evaluating the evolutionary dynamics of impacts, proposing measures to avoid their socio-territorial embedding and accelerating recovery processes. This tool is designed for strategic use by policy makers and managers responsible for flood risk management and regional development.

In Spain, and particularly in the Valencia Region, the scarcity of water resources means that water resource exploitation must be optimized. In this light, reusing the large amounts of treated wastewater is a top priority, especially in agriculture, urban use and the irrigation of golf courses. Rincón de León wastewater treatment plant–water reclamation plant (Alicante, Spain) supplies reclaimed flow to a number of users according to the guidelines stated in the Royal Decree 1620/2007. Reclamation treatment includes: coagulation + flocculation + filtration (sand bed), ultrafiltration, ultraviolet disinfection and desalination (reverse osmosis). By combining these processes, three tertiary treatment alternatives were configured, and for each of them the quality of effluents, treatment costs, energy consumption and the uses of treated water were analysed. The results show that the quality of the water treated using the three alternatives is suitable for different uses. Moreover, the costs resulting from the tertiary treatment processes, their energy consumption and the final price of the treated water paid by farmers have been obtained.

Decision-making in water resources management is a perennial source of political debate. When a basin suffers from a structural water shortage the possible solutions are either a transfer from another basin or the use of other unconventional resources such as those obtained through desalination or water reuse. Politics and territorial interests have given rise to undesired fluctuations in Spain’s water policy, in particular with regard to transferring water from one basin to another. However, conflicts have not prevented water management in Spain from being one of the most advanced in the world, even with its unfavourable geographical context.This work was supported by the Spanish Ministry of Economy and Competitiveness through the project ‘Quality of Aquifers and Agricultural Impacts’ [grant number DER2011-27765]