PARC AGRARI DEL BAIX LLOBREGAT: A CASE STUDY ON THE USE OF RECLAIMED WATER FOR AGRICULTURE
by the Barcelona Metropolitan Area (AMB)
The Barcelona Metropolitan Area (AMB) is the public administration body that encompasses 36 municipalities around the city of Barcelona, the largest metropolitan conurbation in the western Mediterranean, with more than 3.2 million inhabitants in 636 km2. It shares local government powers over transport, environment, planning and socio-economic development. Concerning water management, the AMB is the regulatory body over the integral water cycle activities from water supply to wastewater treatment in the metropolitan territory.
Historically, the AMB suffers from water scarcity and in the current climate change scenario, drought periods are expected to increase. The challenge is to preserve surface and groundwater for water supply and use reclaimed water as an alternative resource for irrigation and other uses.
The Spanish case study of MAGO will focus on the Parc Agrari del Baix Llobregat area, where reclaimed water has been used for agricultural and environmental purposes during the last decade. The site is located about 5 km south of Barcelona, in the alluvial plains of the Llobregat river delta, and currently covers a total of 3,332 ha. The geographical location of the Park determines the characteristics of its lands, located on a fertile plain with high-quality soils affected by significant seasonal variations in temperature and precipitation volumes, inherent in the Mediterranean climate. Thanks to these fertile soils and an extensive irrigation and drainage network, intensive vegetable and fruit farming can take place.
It is essential to mention that this area is severely affected by the salinization of the aquifer; thus, in addition to the amount of water, there is a quality issue. In this sense, although the conflict between agricultural and environmental uses can cause eutrophication in the stagnant areas of irrigation canals, freshwater infiltration should improve the surface aquifer water, severely affected by marine intrusion.
In this context, one of the key actions within the MAGO project will be to improve the management and expansion of the reclaimed water for agricultural uses in this area and to perform a comprehensive approach to the different problems and
opportunities. In particular, task 3.3, in which AMB is the leader, will focus on the use of reclaimed water for agriculture with the study of the risk analysis of these practices considering emerging and recalcitrant pollutants, the cost-benefit assessment at a regional level under different scenarios and the identification of best governance approach in water management in this area.
The project is facing several handicaps, such as the number of actors involved, water quality and hydrodynamic geological characteristics, farmers’ sensitivities and future climate change resources reduction scenarios. Therefore this must allow us to approach all these aspects and facts, from a holistic point of view allowing us to face present and future challenges.