Marine Glossary
Chart Datum
The reference water level from which depths are measured on a nautical chart. In U.S. waters, this is usually Mean Lower Low Water (MLLW).
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Guides6mHow to Read a NOAA Chart: A Practical Guide for New Boaters
Paper charts aren't dead. Learn the 12 symbols every coastal boater must know, how to interpret depth contours, and why your chartplotter can lie.
Captain Marcus Reedupd