Skip to content

Frank L. Engel, Ph.D.

Frank L. Engel

Geographer · Hydrologic Remote Sensing · USGS


I develop and operationalize non-contact surface-water measurement technologies at the U.S. Geological Survey. My work spans image velocimetry, national hydrologic imagery infrastructure, and entropy-based discharge computation — bridging research-grade science with operational field practice at national scale.

  • Image Velocimetry


    Creator of IVyTools — the first operational software enabling USGS to measure river discharge from video. Trained 190+ staff nationwide.

    Learn more

  • National Imagery Infrastructure


    Co-Founding Architect of NIMS — cloud platform serving 1,000+ cameras and 110M+ images for hydrologic monitoring across the United States.

    Learn more

  • Entropy-Based Discharge


    Operationalized the Probability Concept method and built SurfVelTools for computing streamflow from minimal surface velocity observations.

    Learn more

  • ECHO AI Skunkworks


    Founded a rapid-prototyping team evaluating AI-assisted tools for camera imagery and hydrologic workflows.

    Learn more

  • ML Image Velocimetry


    Deep learning frameworks for fully autonomous velocity estimation from river video — collaborations with Penn State and Stevens Institute.

    Learn more

  • Training & Teaching


    National training curriculum for non-contact methods — 190+ staff trained, plus university short courses and graduate advising.

    Learn more


v1.5.0.0

Welcome to IVyTools v1.5 🎉

This is a major update bringing interactive lens correction, smarter search line handling, improved velocity visualization, and friendlier error reporting. Here's the highlights:

Plus: improved orthorectification for portrait/oblique cameras, add/remove GCP rows directly in the table, documentation migrated to MkDocs, and numerous bug fixes for units, uncertainty, and project loading.

Tip: Existing v1.x projects will load normally. Reprocessing is recommended to benefit from the search line clipping and ortho improvements. Older projects using 3D rectification will need to be review, as the new 3D method will be slightly different (XS will move).

Full details in the v1.5.0.0 Release Notes.