Development of the Gap Analysis Tool (GAT) – ERDC

Follum Hydrologic Solutions (FHS) is developing the Gap Analysis Tool (GAT), a modern, Python-based, GIS-integrated application that automates the identification and characterization of wet-gap obstacles such as rivers, streams, and channels. The project addresses a critical need within U.S. Army mobility planning, where legacy wet-gap assessment tools rely on outdated datasets and fragmented workflows. GAT integrates authoritative hydrologic and geospatial data—including National Geospatial-Intelligence Agency streamlines, ensemble streamflow forecasts, and terrain preprocessing methods—to produce rapid, reproducible, and defensible assessments of hydraulic obstacles across diverse environments.

The project benchmarks existing U.S. Army Engineer Research and Development Center (ERDC) gap analysis tools, develops a next-generation automated workflow, and validates performance across multiple U.S. test sites. GAT delivers both GIS-ready spatial outputs and tabular summaries, enabling immediate use by analysts and planners in both secure and unclassified environments. Designed with a modular and extensible architecture, the tool improves transparency, reduces analysis time, and enhances confidence in mobility and flood-related decision-making. Upon completion, ERDC will receive a fully documented, field-tested capability that strengthens hydrologic modeling support for military operations, flood hazard assessment, and resilience planning.