“When navigating in narrow channels or complex waters, the ship's speed must be reduced to a safe level to allow for better maneuverability and reaction time in case of unexpected situations. For example, in a narrow river channel, maintaining a speed of no more than [X] knots is advisable.

A strict lookout should be kept at all times. Crew members on lookout duty need to pay attention not only to other vessels but also to any shoals, rocks, buoys, or other navigational hazards in the area. They should report any sightings immediately, using phrases like 'There is a shoal ahead on the port side' or 'A small boat is approaching from the starboard quarter'.

The ship's navigation equipment, such as the radar, GPS, and echo sounder, must be in good working condition and closely monitored. The radar can help detect other ships and obstacles even in poor visibility, while the GPS provides accurate position information to ensure the ship stays within the safe channel. The echo sounder is crucial for measuring the water depth to avoid running aground. For instance, if the echo sounder shows a decreasing water depth rapidly, appropriate actions like altering course or reducing speed further should be taken promptly.

Communication with other vessels in the area is essential. Use the VHF radio to exchange information about intentions, positions, and passing arrangements. For example, say something like 'This is MV [Vessel Name]. We are proceeding up the channel and plan to pass you on our port side. Please confirm.' This helps avoid misunderstandings and potential collisions.

Familiarize yourself with the local regulations and navigation aids specific to the narrow channel or complex waters. Some areas may have special speed limits, traffic separation schemes, or requirements for using certain channels or berths. Pay attention to the markings on buoys and beacons, as they indicate safe routes, dangerous areas, and other important information.

The ship's steering and propulsion systems should be checked and ready for immediate operation. In case of a need to make a quick turn or stop to avoid an obstacle, these systems must function properly. Also, have the crew ready to handle the mooring lines in case of an emergency stop or if assistance is needed from the shore.

Be aware of the tidal currents and their effects. In some narrow channels or estuaries, tidal currents can be strong and change the ship's speed and course. Plan the voyage according to the tidal schedule and take into account how the currents will impact the ship's navigation. For example, if there is a strong ebb current against the ship's direction, more power may be needed to maintain the desired course.

In complex waters with multiple vessels and various hazards, it may be necessary to assign additional crew members to specific lookout positions or to assist with navigation tasks. This ensures that all aspects of the situation are closely monitored and that the ship can respond effectively to any challenges that arise.”