Présentations Colloques

Los Arenales is an extended aquifer located in Castilla y León, Spain, where Managed Aquifer Recharge (MAR) activities started in 2002. The zone has an important agro-industry associated to this irrigated area. In 2002 and 2003 MAR started at Santiuste basin and Carracillo District, consisting in pioneer passive and intermittent systems which take most of the water from rivers and, consequently, are dependent on weather conditions.**In 2012 a new area, Alcazarén-Pedrajas, adopted MAR as a solution to ensure irrigation supply, with some novelties with respect to previous experiences- the diversification of the source of water, depending not only from Pirón River, but also from the rainwater harvesting from roof tops collected in a MAR canal and reclaimed water from a Waste Water Treatment Plant. All of these sources guarantee that the system is not intermittent any longer, ensuring a certain continuity of MAR further the winter season when river surplus is available for recharging. Anyway, this site presents some problems and impacts to be solved regarding water quantity and quality, e.g. the risk in case of over-floods, the purification process issues, the restricted efficiency rate…**The tests performed regarding modifications in the initial design, such as spillways drawing, use of different filters (gravel, grit, biofilters), DBPs… to improve the recharge water quality, reduce TOD, organic carbon concentration… have driven to a permanent enhancement process where technicians are learning from the experiences to apply new solutions. Other not technical problems have been faced too, especially regarding regulations and conflicts of interest.**In short, the article exposes the diversification of the water source as a key for MAR and describes some of the technical, legal and management problems found, and how they are being solved by means of permanent research and deployments in a constant feedback process.**