COUPLED SURFACE-SUBSURFACE MODELING: BEEN THERE DONE THAT

For more than a decade our group has been engaged in coupled surface / near-surface hydrologic-response simulations using the Integrated Hydrology Model (InHM). InHM is a comprehensive physics-based model designed to simulate 3D variably-saturated subsurface flow and solute transport and 2D flow and solute / sediment transport over the land surface and within open channels. InHM’s first-order coupling facilitates detailed examination of interactions that are not obvious, thereby advancing our understanding of the non-intuitive interplay between processes that are not mutually exclusive. Results and concept-development interpretations from several InHM applications will be discussed, including catchment-scale rainfall-runoff / sediment transport simulations for rangeland sites in Oklahoma and Australia, catchment-scale hydrologic-response simulations used to drive slope-stability estimates for forested sites in Oregon and an urban site in California, watershed-scale hydrologic-response / sediment transport simulations for the Searsville lake / dam area on the Stanford campus, watershed-scale hydrologic-response simulations (focused on cumulative effects) for the North Fork of the Caspar Creek in California, and regional-scale landscape-evolution simulations for the Hawaiian island of Kaho’olawe.