Development of an Engineering with Nature (EWN) Design Tool

The U.S. Army Corps of Engineers (USACE) has a major responsibility for the regulation of the Nation’s streams, rivers, and waterways. This often requires developing water quality models to resolve issues and concerns with regard to the environment and ecosystems. USACE Engineer Research and Development Center (ERDC) is currently developing an Engineering with Nature Design Tool supported by years of research and development in the Gridded Surface Subsurface Hydrologic Analysis (GSSHA) model and a suite of Water Quality and Ecosystem Models (Clearwater Water Quality Modules). GSSHA is a physics-based, distributed, hydrologic, sediment and constituent fate and transport model. Features include two dimensional (2-D) overland flow, 1-D stream flow, 1-D infiltration and unsaturated flow, 2-D saturated groundwater flow, with full coupling between the groundwater, shallow soils, streams, and overland flow. Sediment and constituent fate and transport are simulated in the shallow soils, overland flow plane, and in streams and channels. GSSHA can be used as an episodic or continuous model where soil surface moisture, groundwater levels, stream interactions, and constituent fate are continuously simulated. The fully coupled groundwater to surface-water interaction allows GSSHA to model basins in both arid and humid environments. ClearWater (Corps Library for Environmental Analysis and Restoration of Watersheds), developed by the ERDC, offers a library of environmental simulation software that leverages capabilities of existing water resource simulation models to assess environmental impacts and design solutions to manage and restore aquatic ecosystems. The following Water quality modules are included: NSMs (Nutrient Simulation Modules, I and II), TSM (Temperature Simulation Module), MSM (Mercury Simulation Module), CSM (Contaminant Simulation Module), GCSM (General Constituent Simulation Module), SSM (Solids Simulation Module), and RVSM (Riparian Vegetation Simulation Module). This presentation will discuss current development efforts and future directions in support of a design tool for Engineering With Nature Infrastructure.