High and Low Tides…what should you know

March 30, 2021
High and Low Tides

Tides are the vertical movement of water caused by the gravitational pull of the moon on the earth.  As the moon orbits around the earth it actually “pulls” on the surface causing the water to rise beneath it.  So as the water level rises in some areas it falls in others.  The high tide follows the moon, therefore there are two high and low tides each day.  Note the picture.  See how the moons position affects all four sides of the planet.  Knowing when the tides occur is very important to boaters on Long Island Sound.  You can calculate depth with a watch and a chart!   There are many sources that provide Tide Tables.  There are publications, phone apps, and media outlets that provide us with the information.


Connecticut has a very rugged coastline.  Some areas look completely different at low water depths.  Most importantly, charts always show water depths or soundings, at low tide.  On the other hand, bridge clearences are charted at high tide.  Therfore we have the worse case scenario when navigating.  The difference between high and low tide is called tidal range.  Knowing the tidal range is just as important.  Some areas can have a tidal range of 30 plus feet!  Long Island Sound has an average of approximately 6.5 feet of range.  Its the geographic make up of the bottom and surroundings that cause a vast difference in tidal range.  Above all, be smart, be safe, and remember there are no egos when passengers lives are in your hands.

Please visit our Public Course Schedule to view all of the classes we have availabe for you.  Classes are now done via Zoom.  There has never been an easier way to get your Boating Certificate

Here is a great article from NOAA’s website regarding tides:   What are Tides – Tides and Water Levels: NOAA’s National Ocean Service Education