Proposed recharge of island aquifer by deep wells with regenerated water in Gran Canaria (Spain)

Abstract

Managed aquifer recharge (MAR) and, in particular, recharge by direct injection into the aquifer through wells or boreholes allows for a series of very interesting solutions to solve various technical and environmental problems related to management of the urban water cycle. These problems include the overexploitation of water resources, marine intrusion or contamination of groundwater by irrigation returns. The island of Gran Canaria presents several of these problems; thus, the feasibility of implementing a recharge system has been studied to provide a solution to some of them, using a resource of great potential such as reclaimed water. A detailed characterization of groundwater quality in the study area was carried out, complemented by a field campaign with water sampling from the surrounding catchments, in situ analysis and subsequent laboratory analysis. Specifically, an MBR treatment with disinfection is proposed, where the final conclusions indicate that this is a technically and economically viable project, innovative in its application on islands, a priori with an acceptable productive recharge capacity, possibly scalable after the experimental phase and extrapolable to other locations with similar conditions. In addition, it presents a set of important environmental benefits with respect to conservation of and improvement of the state of the groundwater bodies in the studied area, as well contributing to knowledge of and research into water management in volcanic lands and islands.