With creative solutions and a dedicated team, we persevered through significant access challenges and natural disasters to successfully remove and replace three 96-inch diameter butterfly TSV valves and the adjacent penstock sections upstream and downstream of each unit. We developed a modular barge transportation system to transfer materials nine miles over water to the access point at the base of the dam and custom-engineered handling and rigging systems to safely transport the valves in the low-ceilinged tunnel. We also overcame schedule impacts from fires, floods, and the COVID-19 pandemic to successfully complete this project.