Buoys

Buoys are floating aids to navigation used to mark channels and warn of dangers such as shoals or obstructions. On the chart, lighted buoys are indicated by a purple flare from the buoy symbol or by a small purple disk centered on the position circle.

Buoys are distinguished by color, shape, topmark, lights, and sounds. The colors red and green are used for lateral marks or to delineate the edge of a channel. These can be colored all red or all green, but they can also be horizontally banded red and green or vertically banded red and white.

Yellow is reserved for special buoys which may be used to indicate an unusual area or feature such as traffic separation, spoil ground, military exercise zone, cable, pipeline, or recreation zone.

When you shine a searchlight on buoys at night, reflective tape helps identify them, and the color of the reflective material agrees with the color of the buoy.