The buoys shown below are the most common types you will come across on the Solent and surrounding waters.  If at any time you are unsure of what a buoy indicates keep well clear and find out from one of the Watersport patrol team or MCA Coatguard at Lee on Solent.


Cardinal marks are based on the points of a compass.  They indicate to water users that there is a danger (rocks, sandbar, shipwreck etc) and which way to navigate safely round it.  

For example, the North cardinal marker indicates, "There is danger south of me, stay on my north side!"

Cardinal marks are recognizable by the 2 black cones at the top and are coloured black and yellow.

North Cardinal

Cones point up, bouy coloured black above yellow.

West Cardinal

Cones point towards each other, bouy is yellow with black band.




East Cardinal

Cones point away from each other and make an "E" shape, bouy is black with yellow band.

South Cardinal

Cones point down, bouy coloured yellow above black.




Lateral buoys indicate port (left hand side) and starboard (right hand side).  The port marker is coloured red, and the starboard marker is greenThey mark safe passage into harbours and on the Solent also mark the commercial shipping channels.


Keep clear of commercial shipping and large vessels such as ferries, it makes sense to wait for them to pass, they are bigger than us and more than likely unaware that pwc are in their path...also they may be going faster than they appear!



Special marks are coloured all yellow, many are racing marks used by yacht clubs etc.  Some are recovered through winter and re-located in the spring.  

The yellow buoys to the left and right of the slipway at Lee are permanent and indicate SWIMMING AREA, STAY OUT!

Even through the winter months speed is restricted to 10 knots within 800m of shore.


Diver Down Flags & Buoys

As a boat operator you should:

  • Be able to recognize a "diver down" flag. It can be either a blue and white "Alpha" flag on the diversí boat or a red flag with a white diagonal marking floating in the area of the divers.
  • Always stay at least 100ft away from a diver down flag.
  • Keep a lookout for bubbles breaking the surface of the water. The bubbles indicate that there are divers below who may have strayed from their marked diving area.
Divers Flag: A rectangular red flag, at least 12 x 12 inches, with a white diagonal stripe is used to indicate the presence of a submerged diver in the area. 
Alfa Flag: A blue and white flag, at least 1 meter high and visible from all directions, displayed on the dive boat. 

SMB: This inflatable buoy is a surface marker buoy (SMB) that indicates that a diver is below.   It is a delayed device launched by the diver when ascending from deeper water (6 metres or more). 


Other Marks
Stay away from these markers.  Its obvious what they indicate at low tide...
But at high tide its not so obvious!!!!



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