Geochemistry and Isotope Hydrogeology of the Maracaibo Aquifer System (Venezuela) and Its Implications for Urban Water Supply

Maracaibo is the second largest city in Venezuela, and fewer than 40% of the residentsResidents have a permanent waterWater supply. The existenceExistence of groundwaterGroundwater in the area has allowed the use of the aquiferAquifer for the waterWater supply since the 1940s; however, this area is faced with rapid depletion of the aquiferAquifer and salineSaline waterWater intrusionIntrusion, which would produce a waterWater shortageShortage in the future. Hence, the present chapter aims to evaluate the geochemical and isotopic hydrogeologyHydrogeology of the Maracaibo aquiferAquifer and its implication for the urban waterWater supply. The results of the present study showed the presencePresence of high-salinitySalinity waterWater in the central portion of the study area, resulting from the mixtureMixture with older watersWater that came from the El Milagro and Onia preformations. It is also concluded that aquiferAquifer rechargeRecharge occurs through two mechanisms, (i) local precipitationPrecipitation, primarily associated with September and November rainwaterRainwater, and (ii) lateral flux with provenience of the rechargeRecharge of Perijá Ridge, located in the western portion of the region. The results of this study can contribute to the sustainable developmentDevelopment of groundwaterGroundwater and improve the waterWater supply in Maracaibo city.