A Validation and Comparison of Unique, Analytically-derived Hydraulic Conductivity Datasets Using the Upper Colorado River Basin as a Testbed

Abstract:

Accurate, continental-scale hydrologic modeling is necessary for realistic estimates of water availability at large scales. Growing population and the often difficult to predict hydrologic impacts of climate intensify this need. Computational demand makes the calibration of high resolution, continental-scale, physically based models infeasible. This study improves the modeling of continental-scale hydrology by providing a synthesis of approaches to defining hydraulic conductivity. We derive, model, and validate a suite of approaches to determining hydraulic conductivity at the continental scale, as well as compare the results with published hydraulic conductivity sets from literature. We also study the impact of vertically disaggregating hydraulic conductivity fields with the use of depth-to-bedrock estimates. Here, shallow geologies are underlain by bedrock hydraulic conductivity datasets to simulate natural vertical heterogeneity and deeper water bearing units. This study provides continuous and unique solutions to hydraulic conductivity at the continental scale. The methods used in and the datasets derived by this study provide the underpinning for the CONUS 2.0 subsurface dataset.