Climbers inspect downstream navigation lock gates during an annual lock outage at Bonneville Dam, Mar. 1, 2022. The U.S. Army Corps of Engineers, Portland District technicians perform annual maintenance on the navigation locks at Bonneville, The Dalles and John Day dams during these outages. The series of locks on the Lower Columbia are a vital piece of transportation infrastructure and the Corps performs maintenance during scheduled outages, which ensure that these systems stay open on a reliable schedule. To maintain safe and reliable passage through this valuable navigation system, the Corps coordinates the annual lock closures with inland shippers and cruise lines to minimize impacts to those users.