The waters of the United States are marked for safe navigation by the lateral
system of buoys.
The system consists of a simple arrangement of colors, shapes, numbers,
and light characteristics to show the side on which a buoy should be passed
when proceeding in a given direction.
The characteristics are determined by the position of the buoy with
respect to the navigable channels as the channels are entered from seaward.
Lateral System buoys correspond to the buoys noted on a nautical chart.
The expression "red right returning" has long been used by the mariner
as a reminder that the red buoys are kept to the boater’s starboard (right)
side when proceeding from the open sea into port (upstream).
Likewise, green buoys are kept to the port (left) side.
Red buoys are always even numbered.
Green buoys are odd numbered.
Red and white vertically striped buoys mark the center of the channel and have unobstructed water on all sides. They can also be used by the vessel operator transiting offshore waters to identify the proximity of intended landfall.
Lateral System (As Seen Entering From Seaward)
Port Side Odd Numbered Aids
Green Light Only
Light
Daybeacon
Lighted Buoy
Can
Starboard Side Even Numbered
Aids
Red Light Only
Light
Daybeacon
Lighted Buoy
Nun
Preferred Channel To Starboard
-
Topmost Band Green
Green Light Only
Red Light Only
