Don W wrote in message
news
Rosalie,

I think this is a good subject to explore in more detail. Our
boat is
in a marina with floating docks, so this is something we've
never had
to deal with. How _do_ you tie up to a fixed dock with an
extreme
tidal range?

There are several quaysides with an 8 metre (25 ft?) tidal range
around French Brittany and the British Channel islands.

Moor alongside a ladder! Use that with a temporary spring line
while you sort out your ropes. Otherwise have a ladder aboard, or
learn to fly, or trust the guys ashore to tie good knots.

Use bow and stern ropes plus fore and aft springs. Tie off at the
quay, and make any adjustments at the boat end of the warp. Make
sure the boat end can be adjusted when it's under strain.

Each rope should be at least twice as long as the range of tide.
From top to bottom tide the rope then has to accommodate 10% of
stretch. Do this by allowing 10% slack at high tide, or by using
nylon rope with 2 or 3% slack. Have a griping board between the
vessel and quay, and rig light lines to ensure the slack in your
mooring lines doesn't lift your fenders or the griping board as
the tide falls.

JimB
Yacht Rapaz, sadly for sale, to help pay for that lovely Greek
seaside house we've just bought.
http://homepage.ntlworld.com/jim.bae...cification.htm
jim(dot)baerselman(at)ntlworld(dot)com