The Monterrey Metropolitan Area (MMA), in the State of Nuevo León, México, has had a significant increase in its population and associated urban footprint for decades. From a population standpoint, it represents the second largest urban area in México. Its growth has required increasing infrastructure for the necessary services including public access to potable water, which will continue to increase over time. The supply of water resources for the metropolis comes mainly from groundwater sources. These sources are subject to certain conditions influenced by their geographical location, physiographical characteristics, and the geological environment, having a direct impact on the water recharge system of the regional aquifers. The government of the State of Nuevo León has developed an investment master plan for a water resource, outlined to be completed in 2050, which includes the construction of new dams and the setting up of additional shallow and deep production wells. With a constant annual population growth from one to five percent, additional stresses and vulnerability to this valuable resource will occur. Based on the changing demographics and additional stresses to water resources, it is essential to understand the localized natural groundwater regime extending from the precipitation recharge zones to the individual aquifers that serve the needs of the population. The following study evaluates specific aspects of the water regime (recharge zones and springs), in an area approximately 25 km south of central Monterrey, in the Santiago area of the MMA which is expected to have significant urban expansion in the future. The central portion of the Sierra del Cerro de la Silla, which constitutes the study area is a catchment and infiltration zone for meteoric water. Within the study area, five springs were identified and sampled during the dry season, and the collected spring water samples were submitted for geochemical and isotopic analyses. Field surveys, data collection and interpretation have contributed to the understanding of the water origin and associated physical-chemical characteristics during infiltration through the geological succession and ultimate incorporation into the aquifer. The characterization of the regime through a series of field surveys and the spring water characterization has determined the presence of a low enthalpy geothermal system at the depth, that has the potential to impact shallow freshwater regimes. In addition to contributing to the knowledge of the local hydrogeological system, this study can support the understanding of the vulnerability of the natural resource due to human activity and back up concepts of optimal use and protection.

几十年来，墨西哥新莱昂州的蒙特雷都会区 (MMA) 的人口和相关的城市足迹显着增加。从人口的角度来看，它代表了墨西哥第二大城市地区。它的增长需要增加基础设施来提供必要的服务，包括公众获得饮用水，这将随着时间的推移而继续增加。大都市的水资源供应主要来自地下水源。这些水源受其地理位置、地貌特征和地质环境影响的一定条件，直接影响区域含水层的补水系统。新莱昂州政府制定了水资源投资总体规划，计划于 2050 年完成，其中包括建造新的水坝以及建立更多的浅井和深井生产井。随着每年 1% 到 5% 的人口持续增长，对这一宝贵资源的额外压力和脆弱性将会出现。基于不断变化的人口结构和对水资源的额外压力，有必要了解从降水补给区延伸到满足人口需求的各个含水层的局部天然地下水状况。以下研究评估了 MMA 圣地亚哥地区蒙特雷中部以南约 25 公里的水情（补给区和泉水）的具体方面，该地区预计未来将有显着的城市扩张。构成研究区域的 Sierra del Cerro de la Silla 的中部是大气水的集水区和渗透区。在研究区内，在旱季期间确定并采样了五个泉水，并将采集的泉水样本提交地球化学和同位素分析。实地调查、数据收集和解释有助于了解水的来源和相关的物理化学特征，这些特征是在通过地质演替和最终并入含水层的过程中进行的。通过一系列实地调查和泉水表征对该状态的表征确定了深度处存在低焓地热系统，该系统有可能影响浅层淡水状态。