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Did You Know?

We can measure water depth in meters or feet.
Depth is the distance from the sea floor to the surface of the water.



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Some charts show depths in fathoms.
A fathom equals 6 feet.

How deep is 2 fathoms?

Answer: Two fathoms equals 12 feet!


Why Do People Use Nautical Charts?

People use nautical charts to:

A chart
  • Help boats avoid dangerous rocks and sunken ships.
  • Show how deep or shallow the water is.
  • Show where land and water meet to make the shoreline.
  • Find places on the water.
  • Find the direction (north, east, south and west).
  • Measure distances for traveling to objects and places.
  • Mark underwater objects.

Nautical charts help:

  • Plan long-distance boat trips.
  • Determine the limits of international water boundaries and fishing limits.
  • Find the best routes so that ships do not cross paths
  • Determining where to place mooring buoys and safe anchorage sites.
  • Design places where fish can live.
  • Plan where to put oyster beds.
  • Plan building projects that extends into the water, such as piers and marinas.
  • Determine where to deposit dredge materials.
  • Determine where to place underwater nature preserves called "marine sanctuaries".

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