🔍 Key Concepts

• Western Rivers aids to navigation and what an amber (yellow) light indicates • Meaning of Old River Control Structure on the Mississippi River system • Typical actions required when approaching regulatory or control structures (e.g., dams, control structures, locks)

💭 Think About

• Think about what a flashing amber/yellow light generally signals on inland waters—does it usually mark a safe channel line, a hazard, or a special control area? • Ask yourself what the Old River Control Structure is designed to do and whether vessels are normally encouraged to enter it or kept clear of it. • Consider which choices describe normal river navigation practice versus something you would only do under specific authorization or instruction.

✅ Before You Answer

• Verify in the Inland navigation guidance what flashing yellow/amber lights are used for near dams or control structures. • Check which answer choices involve staying in the main river channel versus entering or approaching a structure/inflow channel. • Confirm which river bank is referred to by right descending bank and left descending bank when traveling downstream.