How to Read a Nautical Chart

Step-by-Step Guide

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   Step 1: Examine and study thoroughly the nautical chart of the specific waters you will be navigating before setting sail.

   If you are sailing in unfamiliar waters, write notes on geographical or waterscape features noted on the nautical chart so you are prepared for upcoming hazards., Once that is done it won't be necessary to locate buoys or markers on the small print of a nautical chart.,, Water depth is noted on nautical charts., Nautical charts show heights of features that boats must clear.,, If you are in U.S. waters, the number will be in feet.
   
   Contour lines give an approximation of where water is getting shallower or deeper., As an example of how buoys are marked, the chart will note a red buoy flashing every 4 seconds at night and measuring 33 feet (10.1 m) tall, visible for 4 miles (6.4 km) and sounding its horn every 15 seconds as follows:
   FL R 4sec 33 feet (10.1 m) 4M "2" HORN.
   
   Or, the designation FL G 4sec 10 feet (3.0 m) 4M "1" denotes a green buoy that flashes every 4 seconds at night.
   
   The buoy is 10 feet (3.0 m) tall, is visible for 4 miles (6.4 km) and carries the number
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   Look on the back of the nautical chart to see many of the symbols noted on the front of the chart. , On U.S. nautical chart legends, 1 nautical mile is about
   1.5 inches (3.81 cm).
   
   A nautical mile is 6,076 feet (2,000 m) (1,852 m).,
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   Step 2: Note your starting point and examine your route

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   Step 3: making mental note of any nautical hazards or geographical features you may come across on your journey.

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   Step 4: Notice all buoys and markers as you encounter them; then keep track of their numbers as they appear.

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   Step 5: Look for objects noted on the nautical chart that will be visible so you can confirm your location as you make your trip.

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   Step 6: Know your boat's draft--the depth from the water line to the bottom of the hull or keel--so you do not venture into water that is too shallow for your vessel.

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   Step 7: Know your boat's height when it is sitting in the water--especially if it is a sailboat or has a bridge--so you will know whether your boat can clear the bottom of bridges and power lines.

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   Step 8: Know your hull's beam or width so you will know if you can navigate locks or narrow bridges

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   Step 9: which are noted on nautical charts.

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    Step 10: Note that water depths on charts are denoted by a simple number.

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    Step 11: Watch for buoys and markers on the charts and as you navigate as they are some of the most important navigational features.

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    Step 12: Measure distance on a nautical chart from the legend.

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    Step 13: Visit the National Oceanic and Atmospheric Administration (NOAA) web site at http://www.nauticalcharts.noaa.gov/ to familiarize yourself with nautical charts.

Detailed Guide

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