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Tidal vs Non Tidal Yachtmaster Mileage

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TIDAL vs NON TIDAL WATERS FOR YACHTMASTER QUALIFYING MILEAGE

We are often asked what is considered tidal waters and what is not?

The RYA definition is quite simple. An area is deemed tidal if published stream, current or tidal range data is available, the influence of which is significant enough to require the effects to be taken into account to plan and execute a safe and efficient passage.

Mediterranean Sea & Black Sea

While every expanse of water is technically tidal the Mediterranean Sea is considered non-tidal. This is because the range is typically measured in cm (not metres) and skippers/navigators do not generally need to consider tidal effects when planning or excusing a voyage. There are a few isolated parts of the Med. that have more tide.

  • Euripus Strait (Greece): A narrow channel separating the mainland from the Greek Island of Euboea features tidal streams reversing direction up to four times a day.
  • Strait of Messina (Italy): The straits between the Ionian and Tyrrhenian seas are well know for strong, distinct tidal currents.
  • Gulf of Gabès (Tunisia): Enjoys the largeste tidal range (up to 1.6m) in the Mediterranean Sea
  • Northern Adriatic Sea (including Venice and Trieste): Experiences larger tides with a range of upto 1m.

While candidates may be able to log a very small number of tidal miles in these and other very specific corners of the Med, it is impossible to complete Yachtmaster Offshore qualifying tidal 60 mile passages in the Mediterranean Sea or Black Sea. Offshore candidates requires at least three of their qualifying passages to be in tidal waters. However passage West of Gibraltar will often fall into the deifination of tidal waters.

Baltic Sea

Liker the Mediterranean, most of the Baltic is considered non tidal as ranges and streams are negligible. Noticeable micro-tides and tidal currents only appear in the narrow Western passages and straits connecting to the North Sea.

Canary Islands

Yes the Canary Islands are affected by tide, buut nothing like the English Cannel. The range is typically 1 to 1.3m, Tidal height and secondary port  information is published by the Admiralty, and should be considered for some coastal passages. Tidal streams exist but at the surface are often overtaken by wind driven currents, The trends of these curents are published.

Caribbean Sea

The entire Caribbean Sea is micro-tidal, meaning it has very weak tides. Many Caribbean Islands experience a tiny change of only 10 to 20 cm between high and low tide. Even the “stronger” regional variations rarely exceed 50cm. If a candidiate is considering presenting a Caribbean passage to an examainer as a Yachtmaster Offshore passage they should  very careful consider the RYA’s definition;-  An area is deemed tidal if published stream, current or tidal range data is available, the influence of which is significant enough to require the effects to be taken into account to plan and execute a safe and efficient passage.

Caspian Sea & Aral Sea

These large inland saltwater lakes/seas that do not experience predictable astronomical ocean tides

Inland Lakes and Rivers

Standard freshwater lakes (like the North American Great Lakes) and rivers above the tidal reach do not have tides; any water shifts are caused by wind or weather, not the moon.

Australia and New Zealand

As a general rule all coastal water and estuaries in this part of the world are tidal. There may be some very unique exceptions.


India Ocean