Water deficit fighting in Catalonia: comparison of intervention actions

Abstract

Catalonia suffers from structural water deficit due to its climate and rain pattern, which is worsened by the fact that most of the population lives in the coastline, where water resources are poor. This situation has led to several difficulties in water supply during drought periods. The region of Barcelona keeps growing enhancing territorial imbalances, and climate change makes drought periods much more likely. Therefore, a good water management is vital to ensure water supply to the population. This project analyzes the regulations and organisms involved in water management in Catalonia, as well as studying the water deficit situation. The Catalan water management plans and programs have been studied, besides, the measures proposed in them to fight water deficit and the achievement of the objectives so far. Water deficit is fought with the pursuit of new water resources, which can be technologically generated or by the improvement of the water quality in the environment and decontamination of aquifers. The two main techniques, which suppose a new production of water resources, are desalination and reclamation or water reuse. The technology used in water reclamation plants and in desalination plants is very similar, consisting on a pre-treatment by coagulation-flocculation, followed by sand filters and microfiltration. Then, water is passed through reverse osmosis filters, where salts and microorganisms are eliminated from the permeate. This water is then disinfected and it can be given several uses according to its quality. Desalinized water is intended for water consumption, and thus, is distributed through water supply systems. However, the current legislation does not contemplate direct human consumption of reclaimed water. Therefore, it is reused for other purposes, such as industrial uses, urban cleaning, environmental purposes or agricultural irrigation. The Camp de Tarragona reclamation plant and the Llobregat desalination plant are two examples of how these technologies have been implemented in Catalonia to fight water deficit, the first in an industrial area and the second in the metropolitan area of the city of Barcelona. The technologies used at each plant are compared as well as the costs of the water produced. Each technology has pros and cons, but both contribute to the production of new water resources that can be given several uses, and contribute to alleviating the human pressure on those rivers and aquifers that are already overused. All in all, regeneration and desalination, not only provide a solution to water deficit, but also allow the improvement of the quality of the water ecosystems