What color is a lighted preferred channel marker?

A lighted preferred channel marker is characterized by displaying both red and green lights as a means to indicate which side of the channel is preferable for navigation. This signaling helps guide boaters safely through channels, especially where navigation may be unclear or challenging.

In practice, if the light on the marker is red, it generally indicates that the preferred channel is to the right (starboard) when entering from the sea, while green indicates that the preferred channel is to the left (port). The combination of both colors on lighted markers helps ensure that mariners can easily identify which direction to proceed.

Markers that feature only red or only green lights do not fulfill the function of indicating preference, and the combination of magenta and blue is not recognized in standard navigational lighting for channel markers. Therefore, the presence of both red and green as lighted markers on preferred channel markers is essential for safe navigation.