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Aids To Navigation

To find our way safely from place to place on the water, we must depend on road signs just as we do on land. The aids to navigation are the road signs of the water. Learning to understand them requires experience and practice. However, the benefit to be derived in being able to navigate safely by using the system is well worth the effort.

U.S. Aids to Navigation

navigation aids USA

The buoys and beacons in this system conform to the International Association of Lighthouse Authorities (IALA) guidelines and are located in IALA region B. In this system, there are lateral and non-lateral markers. The lateral markers indicate the navigable channel by their position, shape, coloring, numbering and light characteristics.  

To navigate safely using the lateral markers, you should pass between the red and green. Returning from sea, the red markers are on your right (red, right, returning) and the green are on your left.


Lateral Buoys and Markers 

In the International system, navigation aids mark the edges of channels to tell which way open water is. They are called day beacons if unlighted, lights if lighted at night, or buoys if they are floating. Some buoys are also lighted for identification at night.

Starboard buoy (red)

Starboard buoy

Starboard buoy at night (red)

Starboard buoy at night

Starboard day beacon (red)

Starboard day beacon

Port buoy (green)

Port buoy

Port buoy at night (green)

Port buoy at night

Port day beacon (green)

Port day beacon

"Red, Right, Returning" tells you to leave the red markers to your right, or starboard, when returning from sea. The green markers are then left on your port side and between is the channel. Be sure to look behind you when navigating a narrow channel to make sure you are not being pushed out by wind or current.

Floating Red markers are called nuns and are cone-shaped. They are numbered with even numbers. Floating Green markers, on the other hand, are called cans and are square-shaped like a large can and carry odd numbers. 

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