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Groundwater is a strategic resource for economic development, social justice, environmental sustainability, and water governance. The Lower Casas Grandes Basin located in the state of Chihuahua, Mexico is in a semi-arid region that has increasing groundwater demands while confronting regional challenges such as adverse climate change scenarios and depleting aquifers. Even though there is official information about the availability of groundwater, comprehensive aquifer characterization is still uncertain and needs interdisciplinary investigation using a diverse suite of tools and multiple data sources. This study presents a multi-technique framework to evaluate potential sites to drill for groundwater resources. The main components of the methodology included: wellhead leveling correction with a differential global positioning survey to define piezometric levels, principal component analysis using Landsat-8 images, application of geospatial tools, geophysics using Time Domain Electromagnetic Surveys and Vertical Electric Soundings and structural geohydrology to define aquifer characteristics. Results show that the application of the framework enhances the possibility of successful drilling for groundwater while saving time and money using “pin-point” positioning for drilling sites as compared to a traditional extensive groundwater exploration approach. Low resistivity values (35 Ohm-m) were found at depths from 50m to 85m at sites where the regional static water level reached 245 m deep adding a shallow groundwater potential at sites where the intersection of fracture trace was identified. This procedure can be used at other sites where limited or minimum information is available for groundwater exploration to reduce the risk of drilling dry wells in complex hydrogeological environments.

We present a comprehensive analysis of water availability under plausible future climate conditions in a heavily irrigated agricultural watershed located in the middle section of the Rio Grande Basin in the United States Desert Southwest. Future managed streamflow scenarios (through year 2099) were selected from among 97 scenarios developed based on downscaled, bias‐corrected global climate model outputs to evaluate future inflows to the principal surface water storage reservoirs, possible future reservoir releases, and groundwater pumping to sustain irrigated agriculture. The streamflow projections describe a wide range of dry and wet conditions compared to the average historical flows in the river, indicating significant uncertainty in future water availability in the Rio Grande Basin. We applied the Soil and Water Assessment Tool to illustrate the impact of climate futures on different components of the water budget at a watershed scale. Results indicate declining reliability of reservoir storage to meet the water demand of irrigated agriculture. The impact of declining surface water can be offset by increasing the pressure on the already‐strained groundwater resources. However, the region should be prepared to use slightly saline (total dissolved solids [TDS] > 1,000 mg/L) and moderately saline groundwater (TDS > 3,000 mg/L) as fresh groundwater in the regional aquifer is depleted within the 21st Century under hotter and drier conditions and status quo agricultural land and water management practices.

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