Estimation and validation of groundwater vulnerability of an urban aquifer using GIS and DRASTIC: City of Monterrey, Mexico

Abstract

The Monterrey wellfield is located in the urban aquifer of the Monterrey Metropolitan Area (Mexico), and has been subject to considerably increasing stress. This area is constantly growing, both in terms of infrastructure and population. The overall objective of the present study is to assess and validate the aquifer’s vulnerability to contamination by applying hydrogeological and hydrogeochemical methods. To this end, four campaigns to measure depth of groundwater were conducted and three water sampling surveys were carried out during in 2018 and 2019, when drought conditions existed. The hydrogeological results show that the groundwater mainly flows from southwest to northeast direction. With regard to hydrogeochemical findings, the type of water was determined by Ca2+, Na+, Mg2+, Cl− ions, which can be altered by SO42− concentrations. A vulnerability map was also constructed using the DRASTIC method, which indicates that the most vulnerable areas were contaminated by anthropogenic influences, where SO42−, Cl−, Fe, Al, and coliforms were present.