Single Point Moorings usually consist of a steel or concrete sinker on the river bed with chain or chain/rope riser to a mooring buoy. There is no reliable or simple formula or recommendation that will allow us to say what weight of sinker will be required for a given size of boat within a specific location. However we always try to give good advice.

Points to consider:

• Size of Boat
• Expected Conditions
• Depth of Water
• Type of Bottom
• Ability to deploy

 Hints and Suggestion – single point moorings:

A. Having decided the sinker weight, make sure that the chain attached directly to the sinker is very heavy duty (we recommend at least 34mm).

B. If on a drying mooring or the Low Water level is shallow, the minimum length of the heavy duty chain should be at least three meters. Long experience has shown that this heavy duty chain is an essential part of a good quality mooring assembly, the weight helps to eliminates much of the damage and wear caused by wave snatch, it reduces the possibility of the sinker being jerked out of position. This heavy duty chain will have a long life span and when it’s time to service the mooring it is easier to remove and replace lighter riser chain when the tide is low.

C. Remember, concrete sinkers loose more than 25% of their weight when submerged, they can be damaged and unless made of very special materials they can decompose or crumble.

D. The sinker shape should include a concave underside to increase suction effect on the sea bed.

E. Where lighter sinkers are used it will help if they can be dug in but it is still advisable to use heavy chain between the sinker and the riser-chain.

You will need the following equipment:

· Sinker

· Heavy duty ground chain

· Riser-chain

· Shackles and Swivel*

· Buoy

*Not required if you use a buoy that incorporates a swivel.