Sailing in shallows means it’s likely that sooner or later you’ll go aground – but if you’ve planned for the eventuality in advance the chances are you’ll either avoid it or be able to refloat yourself, as John Simpson explains

I was born at Leigh-on-Sea, Essex on the East Coast of Britain, part of the Thames Estuary.

Here the tide dries out leaving a mile or so of mud with a three-mile creek, before the deeper Ray Channel.

Considering this was where I learned to sail, you’d think I’d know better than to run aground in the Solent.

The family was excited at the prospect of taking our old 26ft clinker-built wooden boat Blauwe Slenk out again after a two and-a-half year refit, despite the fact she was leaking like a sieve because her topsides were still very dry.

Having spent most of the winter in a half-tide mud berth, her underwater planks had swollen up well.

Furthermore, everything had gone perfectly with the short motor down the Hamble River, and after rigging the canvas a gentle sail from the mouth of the river in Southampton Water was brilliant.

A clinker built yacht moored on a buoy

John Simpson’s 26ft clinker-built yacht Blauwe Slenk

Then I had the crazy idea we should celebrate by taking the boat up Ashlett Creek, where we should have time to have a beer and leave before the creek dried out with the tide (Blauwe Slenk draws 5ft).

My plan wasn’t totally stupid because it was between high waters, Southampton being one of the few places in the world that has two high waters due to geography.

On Springs the tide only drops 5% over 21⁄2 hours, even coming back in again slightly for the second high water, before it all drops very suddenly in the last 31⁄2 hours.

This makes Southampton a great port for big ships.

In addition, I had the bonus of local knowledge.

As an instructor at the time I regularly started my five-day day-sailing courses (on spring tides, noon and midnight HW’s) by sailing up this unlit creek in the dark on a flooding tide on a Sunday evening.

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This gave everyone on the first evening of their sailing course the benefit of three essential things: a sail (or motor) up an unlit drying creek, usually in the dark, an opportunity to learn how to lean a keel boat against a wall and dry it out, and the chance to have a beer in the pub as reward!

Then we’d float off again in the morning.

On the last day of an instructor training week we’d even raced three of the four sailing school boats up this creek very early on the tide.

The only rule was that it had to be under sail: the fourth boat drew too much to participate, so motored up.

The race involved much running aground on the mud and trying to sail the boat off on a rising tide – putting jibs up backstays, hanging out on booms etc in an effort to break the boats off the mud.

The relaxed guy who ran the school came the closest I’d ever seen him to losing his cool when he suddenly realised we were past second high water and still not at the top of the creek.

He must have had visions of all four boats aground, and students joining on Friday evening having to wade across the mudflats to dried-out yachts.

So, I’d had plenty of first-hand experience of Ashlett Creek.

Chart of Ashlett Creek

Chart of Ashlett Creek. Credit: Maxine Heath

Unfortunately, as usually happens when I sail with my wife, it all went wrong through no fault of her own: I managed to stick Blauwe pretty firmly on the mud about halfway up the creek.

Unable to break her off we dried out, with the boat lying down on her side at a typical keel boat angle (40°/50°+) with water pouring in the dry port topsides.

After a very uncomfortable evening as it went dark, with only some water to drink and no food, we finally floated off at about 1 o’clock in the morning.

This involved lots of pumping because of the leaks, and limping back up Southampton Water to our mooring. Needless to say, I wasn’t too popular!

The author’s restored his boat Blauwe Slenk over two-and-a-half years – then ran aground on her first outing!

The author’s restored his boat Blauwe Slenk over two-and-a-half years –then ran aground on her first outing!

The only benefit from my own point of view was that we managed, by wading around in the mud, to remove some of the soft sealant I’d put between the underwater planks to fill up the gaps.

This then allowed the boat a full ’take up’ (ie the wood could finish swelling unhindered by sealant).

Our son Wes, who was 10 at the time, took it all in his stride, although he got very cold towards the end because the boat had little accommodation fitted back then.

I sometimes wonder why Janet and Wes still come sailing with me. I’m sure they must often wonder how I manage to teach anyone to sail!

Lessons to learn from boating in shallow water

If you are going to sail into a shallow place – whether your boat has a lifting, bilge or deep keel – do some forward planning.

This is especially true if you haven’t been to your destination before. Don’t take things too casually like I did.

This kind of gentle creek crawling in tight areas is very difficult to do under sail without an engine or oars.

In a location where you have many bends to follow, the wind may not always be blowing from a convenient direction.

What you’ll need

  •  A large-scale chart or map of the area, whether it’s a tidal creek, inland river, inlet in a lake or coral lagoon.
  • A lead line or sounding pole. At Leigh, where I grew up, the fishing boats used long wooden poles painted every foot in two distinct colours. With a lack of space on a small boat you could paint your wooden boathook handle.
    You’ll note I haven’t mentioned echo sounders: although very useful, they mostly only tell you that you’re aground in very shallow places (unless you happen to have the forward-looking type).
  •  A compass.
  • Tide tables.
  • A plotter (parallel rule, Portland, Breton, whichever you favour).
  • A dry wipe board or a transparent waterproof covered board (for the chart or pilotage map).
  • A kedge anchor (second and lighter than the main one on the boat) with rope attached.
  • A dinghy.
  • A spade, to dig out a channel for the keel or keels when things have gone wrong.

Pilotage guide

The next phase of the planning is to mark up the chart and put it in the waterproof cover, or mark up the dry wipe board.

Either of these can then be used on deck when it’s wet, like a deck slate.

Make sure this is done well before you arrive at your shallow spot, or stop at the entrance.

If you are in tidal waters it pays to arrive well before HW even though there’s a risk you could run gently aground.

A diagram showing a pilotage guide to boating in shallow waters

Pilotage guide: Annotations for entering Ashlett Creek, transferred from a chart to a dry wipe board for use in the cockpit

Provided the bottom is soft (sand, mud, shale, gravel etc.) this shouldn’t matter too much: as the tide floods, the boat will float off.

Rock and coral obviously have to be taken more seriously because of potential damage to the bottom of the boat, but it’s still best to arrive as soon as you calculate you can float over any objects.

Before you enter the shallows, organise the jobs on the boat.

If you have enough crew, have one steering by the rough compass courses, another sounding in the bows and somebody else using the chart or dry wipe board telling the helm which way to go, working as a team.

Proceeding with caution, travel slowly at one or two knots maximum on the first plotted course of your shallow river or creek.

Plumb the depths

Employ the lead line tied to the end of a pole, or use a sounding pole on either side of the bows.

Don’t expect the deepest water to run exactly as the chart or map suggests: there’s a good possibility the channel has moved since it was charted.

A diagram showing Techniques for boating in shallow water. Plumb the depths: Use a sounding pole or lead tied to a boathook

Techniques for boating in shallow water. Plumb the depths: Use a sounding pole or lead tied to a boathook

Try to find where the channel is and travel to the left- or right-hand side of it so you can always turn into deeper water.

Deeper water is usually found on the outside of a bend, especially in tidal waters and rivers, due to scouring effects.

If the wind is strong it pays to try staying on the windward side of the channel, so as to blow off.

Expect to run aground occasionally, but try to do it gently.

If you do run aground, spend a few moments sounding to find where the deep water is, so you know which way to come off.

Running aground

On most small boats, if you run aground gently it is possible to come unstuck by hanging on to the shrouds and heeling the boat over with crew weight or putting up sails and sheeting them in.

This doesn’t work for bilge keeled boats, however.

If you’re certain of the depth and won’t sink into the mud, even jumping off the boat and pushing her off can work!

If you run hard aground you may have to use the kedge anchor, rowed out by dinghy to the deep water, to pull the boat off, especially if she’s a heavy boat.

Running aground: Methods to try for getting unstuck when boating in shallow water

Techniques for boating in shallow water. Running aground: Methods to try for getting unstuck when boating in shallow water

Running the anchor warp to a winch can help.

A friend of mine ran aground in a 26ft bilge keeler and couldn’t get her off.

As bad luck would have it, the inflatable tender on tow then drifted between the keels and the yacht sat down on it with the tide.

a diagram showing Running aground: Methods to try for getting unstuck when boating in shallow water

Techniques for boating in shallow water. Running aground: Methods to try for getting unstuck when boating in shallow water

He said it was like sitting on jelly.

Worried about potential damage to the yacht, he ended up having to stab the dinghy with a knife taped to the boathook!

Watch out for potential hazards such as weed, lines round the propeller, plus engine overheating problems from sucking up something into the cooling system.

You should also be mindful of junk on the bottom such as mooring blocks, outfall pipes and  shopping trolleys.

Worth the effort?

Putting a boat into shallow water with the potential that you might do some damage is not something that appeals to everyone.

But it can be great fun, especially if it’s too windy or rough to go out sailing in open water.

If the reward is some wonderful wildlife, a beautiful, peaceful place or a good pub it can be well worth a slightly challenging journey.

Enjoy reading Techniques for boating in shallow water?

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