Flood Mitigation in Urban Areas through Deep Aquifer Recharge: The Case of the Metropolitan Area of Guadalajara

Abstract

The Metropolitan Area of Guadalajara (MAG) experiences water shortage and overexploitation of aquifers. In addition, it suffers from seasonal flooding that is channeled towards inadequate sanitary drainage, creating a strong negative environmental impact. These problems are rooted in the waterproofing of the urban surface. Many cities around the world have used deep injection wells to recover aquifers and remove surface waters. Certain geohydrological conditions are required for the implementation of these deep injection wells, deeper than 30 m, such as significant surface runoff, acceptable water quality for infiltration, considerable depth in the phreatic levels, and good subsoil permeability. All of these conditions exist in the MAG or could be achieved without significant investment. An assessment is presented exploring the viability for a solution based on this technology, as a strategy to recover aquifers and reduce flooding. The first step was to identify, through map algebra, a micro-basin suitable for this technology. Then, mean runoff volumes were obtained and a stratigraphic profile was carried out based on 19 standard penetration tests (SPT).With these data, a numerical simulation of deep injection wells of different dimensions was performed, providing recommendations for a solution based on these calculations. The results show that both problems can be solved with this relatively simple and cheap technology supporting public health.