Crop production and irrigation: deciding factors of wastewater reuse in Spain?

Abstract

Water scarcity in Mediterranean countries, especially in drought periods, justifies the use of wastewater. The deficit of water resources influences crop productivity and threatens environmental sustainability. The objective of this paper is to analyse whether agricultural production and irrigation area determine the volume of reused wastewater in Spain. To that end, a panel data model is estimated with 187 observations from 17 Spanish regions between 2004 and 2014. The results obtained show that wastewater reuse depends on agricultural variables as well as factors which affect the supply and demand of water. These include the relative scarcity of water resources; the availability of surface water, groundwater and desalinated water; the population; and the revenues collected for sanitation and wastewater treatment. Prevailing economic conditions, however, are not a determining factor. Therefore, there is an urgent need to develop appropriate management systems that guarantee the financing of sanitation and water reclamation services in all the regions that have significant crop production and scarcity of water resources.