NEWS: Understanding Nautical Charts for Safty

News-Press has an article written by Joan and Wayne Church of the Cape Coral Power Squadron on how to read a nautical chart for safety:On a road map it is easy to find where you are and to know what roads to take to get to your destination. However, when you look at a nautical chart, you see a scaled representative of the Earth portraying shapes, distances and directions. You must make your own roads.

A chart shows the nature and form of the coast, the general configuration of the sea bottom including water depths, dangers to navigation, locations and characteristics of man-made aids to navigation and other useful features.

The colors on charts are white, blue, tan and green. The white areas show safe courses to navigate. Blue means shallow water, so check the depths to make sure you do not run aground. Green means shallow water and land will be visible at low tide. Tan shows land and cannot be navigated. Numbers indicate the bottom depth or contours. These numbers are the depth in feet or fathoms. Some charts may also show meters.

Understanding and using the U.S. Aids to Navigation System is an important part of operating your boat safely. The system is a consistent way to mark the waters of the United States and its territories. The system serves the same function as the safety signals and signs used in driving.
Red colors, red lights and even numbers indicate the right side of the channel as a boater enters from the open sea or heads upstream.

Green colors, green light and odd numbers indicate the left side of the channel as the boater enters from the open sea or heads upstream.

Red and green colors or lights indicate the preferred channel. If green is on top, the preferred channel is the right as a boater enters from the open sea. If red is on top, the preferred channel is to the left.

Floating red markers called nuns are cone-shaped buoys marked with even numbers.
Cans are green cylindrical-shaped buoys marked with odd numbers. Daymarks are signs attached to structures such as posts in the water.

The Intracoastal Waterway (ICW) runs parallel to the Atlantic and Gulf coasts from Manasquan, N.J. to Brownsville, Texas. Red, right returning also applies to the ICW markers.
However, how do you know which way is returning? Going generally south on the ICW you would have a red right. There are some areas of the ICW such as the West Coast of Florida where you are actually going north. Still, if you are going from New Jersey to Texas, you are returning. Aids to navigation marking the ICW have some portion marked with yellow. Otherwise, the colors and numbers in buoys and daymarks and lights follow the same system as observed in all other waterways.

The unique yellow triangles indicate aids should be passed by keeping them on the starboard side of the vessel. Yellow squares indicate aids should be passed by keeping them on the port side.

For more information contact the Cape Coral Power Squadron 549-9757.