Introduction

  • The Next Generation Water Resources Modeling Framework (NextGen) advances the National Water Model with flexible, modular, and regionally adaptive hydrologic modeling at national scale.
  • NextGen In A Box (NGIAB) packages the complex NextGen system into an open-source, containerized application for easier access and usability.
  • NGIAB uses Docker and Singularity for portability across local machines, cloud platforms, and HPC systems.
  • NGIAB’s multi-layered architecture integrates hydrologic modeling tools, CI/CD pipelines, and supportive technologies and is complemented by a suite of extensions that allow for end-to-end workflows from data acquisition to visualization and evaluation.
  • NGIAB fosters an open ecosystem where researchers, developers, and practitioners actively contribute new models, extensions, and workflows.

Installation and Setup

  • NGIAB simplifies NextGen framework deployment through Docker.
  • Use guide.sh for interactive configuration and run execution.
  • Always confirm successful setup by executing provided sample runs.

Data Preparation

  • ngen-run/ is the standard NextGen run directory, containing the realization files that define models, parameters, and run settings; forcing data; outputs; as well as the spatial hydrofabric.
  • The Data Preprocess tool simplifies preparing data for NextGen by offering a GUI and CLI for selecting catchments and date ranges, subsetting hydrofabric data, generating forcing files, and creating realization files.

Model Execution

  • To execute a NextGen run in NGIAB with full functionality, use guide.sh in the NGIAB container.
  • A NextGen run in NGIAB can also be automatically executed post-preprocessing using the Data Preprocess tool.

Evaluation

  • Tools for Exploratory Evaluation in Hydrologic Research (TEEHR) is a Python-based backage for hydrologic model evaluation.
  • NGIAB uses TEEHR to assess model performance, comparing predictions against USGS streamflow and NWM data and calculating performance metrics.
  • TEEHR runs automatically with the main guide.sh NGIAB script.

Visualization

  • The Data Visualizer (built on the Tethys Platform) provides interactive geospatial maps and time series plots for NextGen model outputs in NGIAB.
  • It integrates seamlessly with NGIAB via guide.sh or ViewOnTethys.sh.
  • Model outputs reside under ~/ngiab_visualizer, with metadata stored in ngiab_visualizer.json.
  • You can visualize Nexus points, catchment summaries, Troute variables, and TEEHR hydrographs and performance metrics.

Advanced Topics

  • NGIAB supports HPC environments through Singularity, not Docker, but the workflow mirrors the local Docker use.
  • Port forwarding is required to use the Data Visualizer through an SSH connection.
  • Community contribution guidelines are available in each repository’s GitHub page.