Coupling Coastal and Hydrologic Models through Next Generation National Water Model Framework

Abstract

It is important to understand flooding in highly populated coastal regions, especially as the severity of extreme flood events is projected to increase. The integration of inland and coastal models offers an improved representation of flooding phenomena in coastal regions. The Next Generation Water Resources Modeling (NextGen) is a state-of-the-art computational system designed to enable model interoperability and facilitate the study of water-related problems across various scales. NextGen has the potential to couple hydrologic, hydraulic, and hydrodynamic models. This study develops the first Basic Model Interface (BMI) to couple a coastal model (GeoClaw) with the National Water Model Conceptual Functional Equivalent (CFE) hydrologic model through the NextGen framework to expand the initial capability of the NextGen National Water Model (NWM) for interaction with coastal models. In this study, we successfully demonstrate the coupling process of coastal and hydrologic models for Hurricanes Harvey and Ike in a watershed that discharges into Galveston Bay, Texas, using the NextGen framework. This study lacks time series discharge integration in the coupled model but provides a foundation for future work, paving the way for efficient advancements such as two-way coupling.