NextGenSandbox is a workflow tool for setting up, running, calibrating, and evaluating NextGen/ngen hydrologic modeling experiments. It brings together common setup steps such as hydrofabric subsetting, forcing preparation, model configuration, calibration, validation, and large-scale job launching so users can move from basin resources to repeatable simulations with less manual wiring.
For a new machine or first-time setup, follow the install guide. The guide includes a Quick Path, detailed installation steps, and a smoke test to verify the core workflow. For common setup issues, see the diagnostics guide.
NextGenSandbox configuration defines the resources, models, and run behavior for a project. This includes project directory layout, hydrofabric subsetting, forcing preparation, local observations, model formulations and variants, simulation or calibration task types, output retention, and calibration search settings.
Start with the configuration guide for the main field reference. The directory layout guide explains how reusable resources and generated outputs are organized.
Detailed guides are also available for model configuration, calibration settings, and observations/objectives.
After installation, use the project workflow guide to set up a custom single-basin project, run sandbox --subset, sandbox --forc, sandbox --conf, and sandbox --run, and then scale larger experiments with the Sandbox Launcher.
To see the current model formulations supported by NextGenSandbox, run:
sandbox --formulationsSee the formulations guide for model combinations, variants, and setup notes.