The U.S. leads the world in the number of dams built in the last century, with over 80,000 dams higher than 6-feet (USACE), impassable to fish. Few features have impacted natural river processes and fish passage more heavily. While dam removal benefits are high, planning and design is often prolonged and challenging. At NSD, we understand the science, its limitations, and how to engineer solutions that restore river processes and ease passage for migratory native, ESA listed and local fish communities. We have instructed classes in fish passage design, authored current design standards, and designed solutions for perched and steep culverts, shallow flows, and numerous migration barriers.