The first time I deliberately let my boat sit on the bottom, my stomach was in knots. Everything I had been taught said keep the keel off the ground, and here I was choosing to put it there on purpose, in a drying corner of a small Breton harbour, so I could scrub a summer's worth of weed off the hull. The water went away. The boat leaned, settled, and sat there as solid as a house. Four hours later it floated off without a mark. That afternoon turned drying harbour Brittany from a thing I feared into a tool I use.
Brittany is built for this. The tidal range here is enormous, swinging four to six metres over a normal lunar month and far more on the biggest tides, and the harbours empty twice a day to reveal firm sand and clean rock. If you sail a boat that can take the ground, you have access to a kind of free boatyard that the deep-keel fleet can only envy.
What "drying" actually means
Every chart of a Breton harbour marks drying heights. They are printed underlined, and they tell you how far the seabed dries above chart datum. A drying height of 2.0 metres means that patch of bottom sits 2 metres above the lowest possible tide. To float there you need the predicted height of tide at that moment to exceed 2 metres plus your own draught plus whatever clearance you want under the keel.
This is where Mediterranean sailors come unstuck, because in the Med the tide barely moves and a chart datum is almost an abstraction. In Brittany it is the most practical number on the page. If you cannot read a tidal curve confidently, stop and learn it before you try any of this; my piece on Brittany tides for sailors used to a tideless sea walks through the whole business of coefficients and the rule of twelfths.
Choosing the ground
The single most important decision is where you put the boat down, and you make it before the tide ever leaves. A good drying berth needs five things.
The bottom must be firm. Clean sand or fine shingle is ideal. Soft mud lets a fin keel sink and lean unpredictably, and it makes scrubbing miserable because you sink in too. Brittany sailors use drying berths enthusiastically precisely because so much of the ground here is firm sand.
It must be reasonably level, or sloped in a way that lets the boat lean against something solid like a harbour wall. A boat settling on an uneven bottom can drop awkwardly.
It must not be rocky. A single boulder under one bilge will take the whole weight of the boat and can hole you.
It must drain cleanly, not hold a puddle that keeps the boat half-floating and unstable.
And it must be sheltered from swell, wash and the wake of passing boats while you are aground. A boat bumping on the bottom in a swell is a boat suffering damage.
Walk the berth at low water first if you possibly can. An hour spent prodding the sand with a boathook the day before saves a ruined hull.
Bilge keels, beaching legs and fin keels
The easy life belongs to bilge-keelers and twin-keelers. They were designed for exactly this, sitting upright on their two keels with no fuss. Once the water has gone, you put the kettle on or get the scrubbing brush out. France has a whole fleet of these boats and the drying harbours are full of them in summer.
A fin-keel boat can dry out too, but it needs help to stay upright, because a single fin will not balance on its own. The traditional answer is beaching legs: adjustable aluminium poles that bolt to the hull on each side, each with a load-spreading foot and tensioned lines to hold it vertical. The keel takes the boat's weight; the legs only provide balance, so they do not need to be massive. Rig them before you dry out, set them so the boat sits dead upright or leaning very slightly towards a wall, and double-check the bolts.
The alternative for a fin keel is to lean the boat deliberately against a harbour wall, fenders out and lines rigged to hold it in. Plenty of Breton walls are built with exactly this in mind, and you will see local boats lined up against them like horses in stalls.
Timing it with the tide
The sequence is simple once you see it laid out.
Arrive on a falling tide, with enough water still under you to position the boat exactly where you want it. Set your ground tackle or your wall lines, rig the legs if you have them, and let the water leave. As it falls, the boat settles. Once she is firmly aground you can step off, work, walk ashore, whatever you came to do.
Then the water comes back. Be aboard and ready before it floats you, with fenders and lines tended, because a boat refloating against a wall in a fresh breeze needs watching. As soon as you have water under the keel and steerage, you can leave.
The one figure you must get right is the height of tide at the moment of refloat. If you have dried out on a big spring and the next tide is a smaller one, you may not get the same height back, and a boat that grounds at the top of a falling spring can find itself stuck for longer than the crew expected. Always check that the following high water gives you enough to float off, and give yourself a margin.
A worked example
Say I want to scrub the hull in a drying berth that the chart shows drying 2.5 metres. My boat draws 1.5 metres. To sit comfortably aground for a couple of hours I want the tide to fall below about 4 metres, which on a typical Brittany day it easily does. To float off again I need the next high water to climb above 4 metres, which on all but the smallest neaps it will.
So I look up the day's tidal curve, pick a tide where the low water is well below 4 and the following high water is well above it, arrive an hour or so before that low, do the work on the bottom of the tide, and float off on the flood. On a Breton coefficient of 90 or 100 there is no difficulty at all. On a poor neap with a small range I would think twice, because the water might not climb back far enough to lift me cleanly.
A few hard-won rules
Never dry out somewhere you have not seen at low water or cannot trust the chart for completely. Never dry out in a swell or where wash will reach you. Check the bolts and lines on your legs every single time. And remember that the bottom you are about to scrub is the same bottom you would inspect if you were buying a used boat and surveying the hull, so use the chance to look hard at your own keel joint, your antifouling and your through-hulls while you have the boat high and dry for free.
Drying out is one of the great pleasures of Brittany cruising once the fear leaves you. The whole coast becomes a network of free careening berths, and a job that costs a fortune in a boatyard happens between two tides while you have a sandwich on the beach. If you are heading for the granite ports further east, where the harbours sit behind sills and dry hard, the same skills apply on the Pink Granite Coast and the Bay of Morlaix. Learn it once, and the tide stops being your enemy and becomes the most useful tool on the boat.
