When passing through a lock, which light means "approach the lock under full control?"

When passing through a lock, the amber light signifies "approach the lock under full control." This light serves as a warning to boaters that they should be cautious and ready to adjust their speed or maneuver their vessel carefully as they approach the lock. The use of an amber light indicates that while passage is likely safe, there may be conditions that require attention, such as changing water levels, the presence of other vessels, or the potential for operational adjustments within the lock chamber.

Understanding the meaning of the amber light is crucial for ensuring safety and maintaining control while navigating the sometimes confined spaces of a lock. This knowledge also helps in promoting the efficient operation of the lock system, allowing for smoother transitions for all vessels involved.