Water management modeling within integrated hydrologic models: process development and insights on water use impacts throughout the hydrologic cycle

Abstract

Water scarcity is a critical and growing global problem expected to be exacerbated by projected changes in climate. Development of more sustainable water practices and policies to address water scarcities will depend on a comprehensive understanding of the compounding impacts of changing climate conditions and water use activities on water supply and demand. Integrated hydrologic models provide important tools to evaluate water use and climate impacts on the interlaced components of the hydrologic cycle. This dissertation presents new methodologies for incorporating, evaluating, and estimating water use within integrated hydrologic models. First, a new methodology leveraging advances in integrated hydrologic modeling and remote sensing is presented to evaluate and estimate changing water use practices over a historic drought. Next suites of sensitivity studies were conducted using integrated hydrologic modeling to evaluate the impact of model configuration and parameterization on the effects of simulated water use activities. Results from this study highlight the importance of model resolution on capturing hydraulic gradient. Lastly, the combined impacts of conjunctive use of groundwater and surface water in combination with climate warming were evaluated using integrated hydrologic modeling to assess the vulnerabilities of future surface water and groundwater supplies to a warming climate. These results highlight the importance and challenges of including water use activities to assessing the impacts of climate warming or drought on surface water and groundwater supplies.