Boating Basics: On the Water

Western Rivers System

This system of markers is used on the Mississippi River and its tributaries above Baton Rouge, Louisiana, and on some other rivers that flow toward the Gulf of Mexico. The major difference from the U.S. Aids to Navigation System's lateral markers is that navigation markers on the Western Rivers System are not numbered. The numbers that are displayed below the daymark shape are not associated with the right or left side of the channel. On the Western Rivers System, these numbers indicate distance from a river mouth.

Non-Lateral Markers

Non-lateral markers are navigation aids that give information other than the edges of safe water areas. The most common are the regulatory markers shown on the next page. They are white and use orange markings and black lettering. These markers are found on lakes and rivers.

Illustrations	What the Non-Lateral Markers Indicate
	Information Squares indicate where to find food, supplies, repairs, etc. and give directions and other information.
	Controlled Circles indicate a controlled area such as speed limit, no fishing or anchoring, ski only or no skiing, or "slow, no wake."
	Exclusion Crossed diamonds indicate areas off-limits to all vessels such as swimming areas, dams, and spillways.
	Danger Diamonds warn of dangers such as rocks, shoals, construction, dams, or stumps. Always proceed with caution.
	Safe Water Markers are white with red vertical stripes and mark mid-channels or fairways. They may be passed on either side.
	Inland Waters Obstruction Markers are white with black vertical stripes and indicate an obstruction to navigation. You should not pass between these buoys and the nearest shore.
	Mooring Buoy Another kind of marker you may encounter is the mooring buoy. These are white with a blue horizontal band. They are found in marinas and other areas where vessels are allowed to anchor.