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Aids to Navigation

Aids to Navigation Systems

Depending on where you boat in America, you may see several differences in how navigational marks are colored, numbered, or lighted. Regardless of the location, buoys and beacons are placed in very specific locations, to mark either a particular side of a waterway, or some other navigational feature. The primary system in use is referred to
the "U.S. Aids to Navigation System". The U. S. Coast Guard maintains this system in conformance to the International Association of Lighthouse Authorities (IALA), which is an international committee which seeks to ensure safe navigation, primarily through the use of common navigation aids and signals.

The "LATERAL" system is the familiar RED RIGHT RETURNING system, meaning that on all navigable waters
returning from sea, the red even-numbered marks are on the starboard (right) side of the channel and the green
odd-numbered marks are on the port (left) side of the channel. Numbers on the marks ascend when traveling from
sea to harbor--if you don't have a compass and become disoriented on the water, you will always know you are
heading upstream if the buoy numbers get larger as you travel.