Navigation

Aids to Navigation and Their Meanings

green
A Can Buoy marks the right side of the channel Leaving a harbor. It will be Green and have odd numbers on it. Green Daymarkers are often used in shallow areas for the same purpose.
If the green marker has several pilings supporting it, it will be called a Dolphin. Green Buoys with lights will usually be found in deeper waters. The light will be green. Larger Buoys may also have bells, horns or other sound producing devices.
Nun
A Nun Buoy marks the Left side of the channel leaving the harbor. It will be red and have even numbers on it. Red Daymarkers are often used in shallow areas for the same purpose..
If the red marker has pilings supporting it, it will be called a dolphin. Red buoys with lights will usually be found in deeper water. The light will be red. Larger buoys may also have bells, horns or other sound producing devices.
green_over_red_daymark
Preferred channel markers are a combination of red and green. Years ago, this marker was known as a junction marker.
Preferred channel markers are a combination of red and green. Years ago, this marker was known as a junction marker.
That is, if the top color is red treat it as a red marker. Just as with red and green markers, they may be found as daymarks or floating buoys. They will have the same color light at the top color of the marker, and they may have letters, but not numbers.
safewater
Preferred channel markers are a combination of red and green. Years ago, this marker was known as a junction marker.
Preferred channel markers are a combination of red and green. Years ago, this marker was known as a junction marker.
That is, if the top color is red treat it as a red marker. Just as with red and green markers, they may be found as daymarks or floating buoys. They will have the same color light at the top color of the marker, and they may have letters, but not numbers.
special_purpose
Special purpose markers are Yellow and may serve a wide range of uses. These may include, but are not limited to, dredging, fish trap areas, spoil areas or Military excercise areas.
range
Range Markers are found in pairs with one higher than the other. Range markers indicate the center line of a channel by having them lined up as you pass through the channel They will have vertical colored panels to assist you in lining them up.
Some markers have no lateral significance. They are not designed to indicate the channel, but rather to help you know where you are.
danger
White markers and or buoys with an orange, diamond, circle, or square can be used to provide information or regulations such as a no wake zone or a shoal area.. As with all other aids to navigation, they should be given a wide berth to avoid possible damage to your vessel.
U. S. Aids to Navigation System (ATON) Buoys and markers are the “traffic signals” that guide boat operators safely along some waterways. They also identify dangerous or controlled areas and give directions and information. As a recreational boat operator you will need to know the lateral navigation markers and non-lateral markers of the U. S. Aids to Navigation System. Lateral Markers These navigation aids are used to mark the edges of safe water areas; for example, to direct travel within a channel. They use a combination of colors and numbers which may be applied to buoys or permanently placed markers.

Aids To Navigation

Waterway Marking Systems Channel Buoys.

Lateral System (Federal)

The waters of the United States are marked for safe navigation by the lateral system of buoyage. This system employs 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.
The expression “red right returning” has long been used by the seafarer as a reminder that the red buoys are passed on the starboard (right) side when proceeding from the open sea into port (upstream). Likewise, green buoys are passed on the post (left) side, Conversely, when proceeding toward the sea or leaving port, red buoys are passed on the port side and green buoys on the starboard side. Red buoys are always even-numbered. Green buoys are odd-numbered. Red and white vertically stripped buoys mark the center of the channel.
Mooring to Buoys Tying up to or hanging on to any navigation buoy (except a mooring buoy) or beacon is prohibited.

Aids to Navigation

In recent years, modification to certain aids to navigation located on coastal and inland waters have been completed. These changes apply to aids used in both the lateral and state waterway marking systems. See charts that follow:

Uniform State Waterway Marking System

uniformstate_marking

Federal Channel Marking System (Lateral System As Seen Entering From Seaward)

fed_channel_marking_sys

Inland Navigation Rules Of The Road

NAVIGATION CHART NOTES
SCALES & SOURCES
Chart Sources:
COLORS:
LETTERING:
CHART DATUM
CHART TYPES
Signals For Restricted Visibility
Not under command
No Signal Required:
Pilot Vessel (Rule 35j) and (Rule 35h INL) HORN 5 SHORT - - - - -
A towed vessel if manned (immediately after towing vessel signal) (Rule 35e INT)
First three signals above are not required for vessels anchored in a special anchorage area designated by the Secretary for:
INT = International Waters
A Free online navigation course. A Great deal of useful information about navigation.
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