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Anchoring & Mooring

Scope

Scope = Length of the anchor line/ height of the deck cleat to the sea bed.


Before leaving the dock, you will need to determine how much anchor line, or "rode", you will need.
It is recommended that you use a scope of 7:1, meaning that for every foot of water depth, you should
use 7 feet of rode.



For example, to anchor in 10 feet of water, you would pay out 70 feet of line. Measure the scope as the ratio
of the length of the anchor rode to the height of the bow above the bottom.  If you're using a lightweight anchor
on a small boat in good weather conditions, a shorter scope of 5:1 is sufficient and safe. A prudent boater
always has extra line and chain on hand, just in case!

The table below suggests minimum working rode sizes:

Anchor table


Suggested holding sizes assume fair holding ground, scope of at least 5:1 to 10:1, and moderate
shelter from high seas.

Boats that operate generally in shallow waters, as on the East Coast of the United States, may get by
with shorter rode lengths. As the wind picks up, deploying additional line will help maintain position,
as will tossing out an extra anchor.