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Re-floating techniques after running aground



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What is the issue?
Always embarrassing, but seldom disastrous, every now then you will run aground. It is part of the life of an adventurous cruising sailor. However heavy seas or uneven ground can make the situation dangerous and many vessels, large and small, have been broken up by running aground in rough weather.

Why address this?
Extensive equipment and vessel damage can be sustained if a grounding incident is badly handled. The vessel may go on to be lost if subsequently caught out whilst aground. This could easily happen if you are unlucky enough to be neaped, where you have grounded on the height of a spring tide and have to wait until the next cycle of spring tides to achieve sufficient draft to get away.

Having a range of techniques to safely re-float a grounded vessel is a key maritime skill and in this article, the long-established practical seafarer Salty John, who specialises today in a select collection of tried and tested sailing equipment External link, shares his experience, augmented by those of the site's founder Michael Harpur, to provide several techniques to help you get the boat clear.

How to address this?
Few people would admit to being an authority on running aground, but I don’t mind doing so. In my defence, I can point to the many miles I have travelled in shallow water with a deep draft, and to my tendency to be both adventurous and optimistic when it comes to exploring off the beaten path.

The 'lean of shame' is more embarrassing than fatal
Photo: Gordon Brown via CC BY-SA 2.0
Although I first ran aground in Scotland many years ago, it was in traversing the Intracoastal Waterway in the USA that I perfected my art. Eight trips on the 1,200 miles of the East Coast Intracoastal dragging 1.85 metres (6 feet) of keel under me meant groundings were almost inevitable. Chesapeake Bay, with an average depth of less than two fathoms (3.66 metres), provided plenty of opportunities for me to take to the mud and even the Vaal Dam in South Africa has felt my keel. I have run aground several times in the Bahamas; once it was a bizarre situation on the Great Bahama Bank in which I was out of sight of land but had my keel buried in the sand.

If that was the strangest grounding then the most damaging was the time I hit the spoil bank on one side of the Houston Ship Channel in Texas. There are few opportunities to cross the spoil banks which line the edges of the channel and I was feeling quite pleased with myself for having found the gaps and crossed in front of a super-tanker steaming up to Houston. I reckoned without his wake, however.

The tsunami being pushed ahead of the tanker picked the boat up and dropped it into the shallow water behind the wave. We hit the bottom with spine-compressing impact; like being dropped from a boat lift onto a concrete dock. It was unfortunate that at this time I was sailing a fin-keeled light displacement French design. Although I appeared to have survived unscathed at the time, I subsequently discovered that the hull had cracked alongside the keel. The first clue was a steady trickle of water into the bilge which could be seen to accelerate when the saloon table pedestal was wiggled.

Happily, this is the only damage I have sustained in all my groundings. So here is what I can share from all the times that I have hit the skids.


A GROUNDING KINDLY BOAT

The first advice I can give, after the light displacement fin-keel is to try not to have this style of a vessel if you are likely to run aground. Have a boat that can take the ground safely. A full keel, heavy displacement cruiser, of the type I owned before and after the ill-fated French racer, will stand up to a terrible punishment. I’m not suggesting that your choice of the boat should be based on performance on land rather than sea, but it is a consideration if you intend to dry out, deliberately or not.


GROUNDING

When you run aground it takes a few seconds to comprehend what is going on; the boat grinds to a halt for no discernible reason; the rig might judder alarmingly; the skipper and crew lunge forward as if on a train that has hit the buffers; the dinghy, if towed, crashes into your transom and, if the engine is running, gets its painter tangled around the prop. You then know immediately what has happened.


FIRST STEPS

As soon as you realize you are aground – STOP! Put the engine into reverse if it is safe to do so. If sailing, slip the sheets to kill the drive. Do not gamble that if you continue forwards you will ride over the obstruction into deep water again. This NEVER happens. The only direction in which you can confidently predict there is deep water is that from which you have come.

There may, in fact, be deep water ahead of you, or on one side or the other, but at this point in the development of the grounding you have no idea where the deeper water lies, or you wouldn’t have gone aground in the first place. A long boat hook or lead line will help you seek alternative sources of deep water later, but at this point, you know only that there is some in the direction from which you have arrived aground. The grounding experience itself will also provide an indication of the type of bottom you have come up upon. Slow deceleration means your into slime or mud, quicker deceleration could mean gravel, abrupt is sand and a crashing juddering halt is a rock or the remains of a wreck.

My first action, if I am motoring, is to go into reverse gear and try to back off. This is frequently successful. Check there are no lines over the side before engaging the engine and if you are towing your dinghy the chances of success are diminished because you have to factor in the possibility of getting the painter around the prop. If you want to tow your dinghy or keep the tenders line out of its own outboard prop, use a floating polypropylene line or a buoyed line Experience. Without the danger of the prop getting fouled by the dinghy painter you can give it some welly in reverse and save the day.

It sometimes helps to steer the boat from side to side to release the keel if it is embedded in mud. If that doesn’t work, select forward and try turning hard to port then hard to starboard. This might loosen the mud’s suction on the keel or dig a hole in the shingle, thereby allowing you to break free by selecting hard astern again. Be careful if your rudder is not fully supported because it is now that it is most vulnerable to damage.

If, however, you are tacking up a channel and pushing it too close to the edge, a common cause for sailboat grounding, try using any remaining momentum the boat has to tack and get the bow through the wind. Generally speaking, the genoa can be relied upon to haul the bow away from the wind and
the main to bring it up. Then sheet the sails in hard to increase heel and reduce draught, or spin the bow further off the breeze to go back down your track into deeper water. Whatever it takes, tacking, leaving the jib backed or gybing, try it all and if you can increase the heel in the process, thereby reducing the draught still further, you will stand a better chance of getting the boat off. Going aground when going downwind allows some heeling latitude as the boat was probably sailing upright.

It is also worth trying to heel the vessel both ways if you are wedged parallel to the contour. Heeling the mast away from the shore reduces draught but it can cause the vessel to drift in and onto a higher gradient and heeling it towards the shore means the keel may slide down into deeper water. In all cases it’s essential to have a strategy in place to move the boat away from the shallow water – for example, kedging as set out below, or going astern under sail or engine.

Bilge keel boats and some wing keel boats cannot be freed by heeling sideways because their draft increases when this is done. Such boats must be forced down at the bow to reduce draft and the best way to achieve this is by having the entire crew stand on the foredeck.


USING READILY AVAILABLE RESOURCES

I have had some success with induced heeling but it isn’t as easy as it might seem in theory. A heavy displacement boat is unimpressed by the crew simply standing on one side deck, unless you are taking the local rugby team for a sail. If you have a boatload of people it is worth a try as you may be able to quickly deploy them to some effect.

First off, make sure everyone gets into a lifejacket and, where possible, switch the jacket triggers to manual release. If you are going to use them to free the boat they will be running about and hanging over the ends of the boat, in and out of the tender, all the time running a very good chance of falling in. The surrounding waters may be shallow enough for them to easily quickly gain a footing but they could just as easily be swept away by a current and the lifejacket will keep them safe long enough to be retrieved.

The first approach is to get them to run from side to side which has often freed a boat locked in the grip of mud or sand. Alternatively having them congregate in the bow or the stern, depending on which end needs unweighting, might be enough to set you free. Having the crew stand on the bow is particularly effective on long-keeled yachts as the keel is often significantly deeper at the stern than at the bow. Another approach is to have them hang onto the shrouds and lean over to induce heel.

Most all of this will have limited effect as you truly need some leverage to get any real heel and you can have more effect if you use the boom as a lever to do this. That means applying the topping lift and getting something heavy out on the end of the boom – a bucket of water, the anchor, a partially-filled dinghy or, the best option is a fit, agile, heavy and, preferably, willing crew member. I’ve never had one of these to hand so have usually undertaken the task myself. Shimming out and hanging myself off the end of the boom got me away in New Zealand's Bay of Islands.

Another recommended technique is to rig a bridle for lifting the tender off the end of the boom, fill it with water and then try to lift it with the topping lift or with a halyard taken to the boom end. This should allow you to significantly heel the boat. With the boat heeled and the draft reduced, motor or tow the boat towards deeper water.

Another key way to get the boat off the bottom is to reduce draught. Lightning the boat could help. If you have full water tanks of water immediately turn on the taps and drain the tank. This lightened my vessel enough to allow me to continue merrily on my way into Sparkes Marina at the bottom of a low spring tide. Other candidates for offloading are heavy objects such as the liferaft, jerry cans, outboards and spare crew, into the dinghy. This can be used to great effect if you deploy two methods simultaneously, both reducing draught and inducing heel by attaching the dinghy to the end of the boom, as described above, and using all that weight. Make sure your bridle is up to it because you don’t want to lose the tender’s contents. It is worthwhile having a dinghy hoist bridal Experience already made up that can be quickly deployed and used in several different ways aboard.

Many of these approaches make very little difference to the draft or heel of a vessel but if you react quickly enough the slightest difference may be all you need to get free. A happier situation would be that you have run aground on a rising tide in which case, as long as you can stop the boat being driven further on as the tide rises, it is just a question of waiting and giving the boat a try every 20 minutes or so. If you get off remember to double check the raw water intake filter after you reach deep water. The harder you push the throttle, the more mud, silt and sand you will have stirred up. This sensitive strainer could well be clogged.


KEDGING

Described in the 1904 Royal Navy’s seamanship manual as ‘a means for manoeuvring large engineless ships in and out of tight harbours and tidal river entrances’ kedging is one of the most powerful weapons in the sailor’s armoury when aground. Kedging means an anchor is carried out by tender and set in deeper water. It is then pulled from the boat by a winch or windlass.

Unfortunately, the requisite long lines and anchor takes some time to get set up, it is laborious, needs a tender and is messy. This is often the last resort and the time it takes to set up does not help but it usually will do the job.

Kedging works best with a long line. Unlike anchoring, it is scope rather than the weight of the ground tackle that provides the holding power. Hence the vessels main anchor and its all-chain rode will be too heavy to manhandle and difficult to handle in a tender. Instead, use a lighter secondary anchor with a short length of chain. If you don’t have a dinghy you can try swimming an anchor out, but it is rarely successful. I’ve tried supporting the anchor on floatation cushions and swimming it out but this is futile because the weight of the chain you are dragging behind simply stops your progress when you have gone a depressingly short distance. Without being able to deploy sufficient rode the whole exercise is doomed to failure.

Before kedging, determine which part of the boat would be easiest to free and where the deeper water lies. Then lower the anchor and all of the chain gently into the sole of the tender and only pay out the line when making your way to the anchoring position. Otherwise, the chain's catenary weight, hanging between the dinghy and the boat, will serve to continually pull you back towards the yacht. Those rowing out a kedging rode in a hard dinghy often have an easier time of it. The long lines and propellers are a bad mix so it is best to motor away in reverse paying out the line over the bow as you go.

There are four broad approaches to kedging:

  • 1. Mast Head Kedge: The objective of this approach is to row the boat out abeam of the vessel and attach the end of your kedge rode to a halyard. A spinnaker halyard’s swivel fitting works well for this - if you don’t have a spinnaker halyard you cannot use the method because the other halyards are likely to jump out of its sheave. Then winch in the halyard using the mast as a lever to heel the boat. This is an extremely powerful way to induce heeling motion in order to dramatically reduce draught. To use this technique you will need a particularly long line kedge otherwise the steep angle from the masthead will only serve to break the anchor out. Just don’t put too much strain on the line; you don’t want to damage the rigging or jam the block at the masthead.

  • 2. Hauling Kedge: Deploy the kedge in the direction in which you would need to move the boat. Then use a cockpit winch or the anchor windlass to try to pull the boat off the mud. The cockpit winch is usually the most successful, as you can pull the boat back towards the deep water from which you came.

  • 3. Twisting the boat around: In soft mud, the twisting action of pulling the bow round can be a good way to break the suction holding the keel. If you have a powerful electric windlass, give the throttle some revs in neutral and very gently try to haul the bow around towards deeper water. Someone needs to be below to keep an eye on the keelbolts if you are in a fin keeled vessel. Twisting the boat around like this will stress the keel root so keep a close eye on the keelbolts and stop winching if there are any signs of failure.

  • 4. Dual Kedge: This is a combination of options 1 and 2 above. Using the second kedge to winch yourself out of the mud, whilst using the leverage from the masthead to heel the boat over far enough to get her off.

Kedging is made slow by the anchor arrangments. If the grounding happened in a mooring area you may be lucky enough to be able to find a mooring buoy that can be used instead of setting an anchor. So keep an eye out.


ANOTHER BOAT COMES ALONG

Sometimes you can get a helping hand from a passing power boat by getting them to purposely wake you as you call upon the engine to produce full power astern. Their wake can give you that little push that does the trick.

Failing this, if pride permits, you can simply ask a good Samaritan for a tow. Make sure it’s your line they take hold of to avoid any potential salvage issues. Likewise, don’t assume that the person offering you a tow is an expert, and they may be running the risk of grounding their vessel. So think carefully about how you would like to use their offer of assistance. Warn them as to where the shallow water is and it may be also worth suggesting that they trim their outboard up to keep it clear of the bottom. Discuss what you would like to do, and arrange a system of hand signals so that you can ask them to start, increase power, reduce power, stop or change course.

A survey then of the situation will help with the lead line and the dinghy. The idea is to find out the nature of the seabed in the immediate area, is it shelving to the shore or a narrow spit? Do you need to come off in exactly the direction you came, taking advantage of the furrow your keel has probably ploughed in the mud or sand, or could you twist off by finding some way to move the bow around?
You generally have two options:

  • • Towed out stern-first the way you came in. Being towed stern-first is generally the kinder option, although like backing the main, it will tend to pull the stern deeper into the mud. Crew weight on the bow can help here. Most boats will need to rig a bridle between the aft cleats in order to spread the load, and it’s a good idea to keep one end of the bridle to hand ready release it from the cleat and let it go should you feel that the vessel is likely to be damaged and you feel the need to drop the tow in a hurry.

  • • Twist the boat off and out by taking a line from the bow. The same applies when towing from the bow: cleat the line with a couple of turns, but be ready to release it if you suspect trouble. This approach will place significant force on a fin keeled vessels keelbolts. Keep an eye on them and drop the line or cut the power if any problems are encountered.

If you plan to help with your own engine, ensure that there is no way you could snag the towing line with your own propeller. The motorboat’s throttle must be used gently and cut completely if you can motor free.

Finally, bear in mind that the forces involved can be considerable. Use the thickest line you have, only make fast to strong points on board and make sure that the crew are clear of all lines. And if it becomes obvious you are not going to move, know when to say stop.

SCOURING AWAY THE SAND

The people that have the most experience with grounded boats are the operators of the various rescue boats belonging to commercial towing services located up and down the Intracoastal Waterway. A subscription to a service such as TowBoatUS is money well spent if you are contemplating the ICW run for any distance.

I was once hard aground near Wrightsville Beach and after failing to free myself with the usual techniques at my disposal I checked my policy and called in the experts. The bright red rescue boat was quickly on the scene and assessing the situation. The bottom was sandy and my keel was seriously buried. The skipper of the towboat then delivered a piece of advice that I wish another rescuer some years earlier on the Neuse River could have heard ‘Take it slow and gentle; no-one gets hurt and nothing gets broken’.

He positioned his boat amidships of mine and stern towards me. He took lines from each of his aft quarters to my bow and stern. Then he ran his two big outboard motors so that they gently blew away the sand around the keel and in ten minutes or so we drifted free: no-one got hurt and nothing got broken. Of course, had it not been for my TowBoatUS insurance policy, it would have hurt my wallet to the tune of $400.

Masthead towing
Photo: CC0


MASTHEAD TOWING

A very effective heeling method is the masthead tow. In this process, the rescuing boat, hopefully, operated by someone who knows what they doing, takes your halyard and heels the boat.

  • • One variation of this system is that the rescue boat, or a crew member in your own dinghy, provides only the heeling motion and the stranded boat provides the motive power to move off into deep water.

  • • Another variation, where the stranded boat cannot provide motive power, is that the rescuing boat takes lines from bow and stern of the stranded vessel and very carefully pulls in the appropriate direction whilst heeling the boat with the halyard.

My first experience with the latter method was on the Neuse River in North Carolina and it turned out to be the most frightening experience of my sailing life to that point. I had called for help after I’d been forced to shut down the engine when the raw water intake strainer had become clogged by all the mud and debris churned up by my attempts to save myself.

A skiff with a powerful motor was despatched from a local marina. We were working against the time constraint of a rapidly falling tide and this seemed to pressure the rescuer into ill-considered action. The rescuing boat had my halyard and we were heeled to the point where the rail was submerged and water was sloshing into the cockpit. This made it difficult and tediously slow to prepare bow and stern lines. Probably fearing he would miss cocktail time at the marina our rescuer decided to just drag us sideways by the masthead halyard rather than wait for the tow lines. We did, in fact, slide off and come upright in deep water, rig intact - but I think this was due to good luck rather than good management.

Aground on a falling tide
Photo: Phuket@photographer.net



YOU ARE TRULY STUCK AND OUT OF LUCK

Ok, let’s say you have driven on hard and no amount of reversing or kedging will get the boat loose. If you have run aground on a high spring tide with an onshore wind it might be months before you can refloat her yourself! The next course of action is damage limitation. You must stop the situation from getting worse for the crew and the boat.

A call to the authorities at this point would be prudent. Make them aware of the situation, the boat position and details, how many are on board, how safe you and your crew are, and they will seek to establish a working channel. If you are on a rocky bottom, make sure they are aware that you will need to abandon if a rock pierces the hull. But always remember the coastguard, though they cannot be more helpful, their job is to save lives, not boats. The next course of action is for you to secure your position.

Drop all sail, lift the cabin sole, check for water ingress and make sure the keel bolts are secure. If the tide is falling you can do nothing about it, unless you have more influential friends than I do, but you can mitigate the effect. If there is a preferred direction for the boat to lay – keel towards incoming waves, perhaps, now would be the time to take action. The particular situations that put the boat in peril and need to quickly remediated are a follows:

  • • Aground with the wind or current driving you further into the shallow water. Get an anchor out towards deeper water, and this is where the dinghy you were towing comes into its own.

  • • You have run aground on a bank on the ebb and the boat is leaning so as to fall over with the mast horizontal or pointing down the slope. Then, when the tide turns, down-flooding becomes a real issue as when the rise comes in through any open vents it will fill the boat. Use the kedging technique from the halyard to heel the boat inshore to prevent this.

  • • The boat has come down on uneven ground and is starting to settle or, far worse, pound upon something that could hole the hull. Use the kedging technique to make her lay more safely. Or, failing that, quickly get some protective padding in place. This could be cushions, sail bags full of non- buoyant boards that may be lashed in place, or even a half-inflated dinghy with its painter lead around the bottom of the hull - fenders are usually ineffective here as their buoyancy tends to make them lift away and out of place. If on the perimeter of a shipping channel, where their wakes are exacerbating the situation, hail passing ships on Ch16, or bridge-to-bridge Ch13, and ask them if they could slow down.

Secure all hatches and cockpit lockers and seal them off. Close all the cocks and tap a bung into the exhaust outlet as with the boat heeled the swan necks may no longer be relied upon. Use duct tape to seal the freshwater, fuel breather pipes and heater outlets as required. Finally, hoist the aground signals which are three black balls by day, two all-around reds at night indicate that the vessel is aground.

Once you are happy that the boat is as secure as it can be, you can redouble your efforts to get her free when the conditions lend themselves to recovery. To assist the towing or motoring off process you can try to reduce the draft of the boat by heeling it one way or the other.


IN CONCLUSION

So that's my experience to date. Provided you refloat without any damage, it doesn’t much matter how you get off. The aim of what we have discussed is to help you react quicker and have a wider repertoire of approaches that might prove more effective. On a falling tide that might make the difference between a nuisance and a nightmare. To summarise:

  • 1. Recognize that you are aground as soon as possible and stop forward motion.

  • 2. If motoring, check for lines in the water and go into reverse immediately if it is safe to do so. Be aware that your rudder is vulnerable when backing up in shallow water.

  • 3. If sailing, tack, gybe or whatever and try to use the last of the momentum to get her out.

  • 4. Reduce draft by heeling the boat. A very effective method is by pulling on a masthead halyard. Another method is putting weight onto the end of the swung out boom; a crewmember or a flooded dinghy being the main candidates. Motor or tow the boat off into deeper water.

  • 5. If this fails, limit the damage by getting an anchor out to windward. If possible orient the boat to provide the most protection from wind or waves.

  • 6. Seek assistance from the professionals, or hail a passing Good Samaritan.

  • 7. Running your engine in shallow water when aground churns up the bottom. Check your raw water intake strainer; if it is filled with sand and mud check your raw water pump impeller for damage.


AFTER A GROUNDING

Hitting sand underwater is like crashing into concrete as I discovered. The harder the strike the more likely the vessel will be damaged. So make certain the vessel is seaworthy afterwards.

  • Keel Checks: Check properly in the bilges for weeping around the fastenings. Lead keels absorb the shock somewhat but may need to be professionally straightened afterwards. Cast iron keels, push the impact back into the vessel so it important to check for signs of stress crazing around the gelcoat where the keel joins the hull and at and around the keelbolts. The most likely locations for damage are at the front and rear of the keel. If at first inspection there appears to be no damage periodically check back from time to as hairline cracks can take time to make themselves visible. Look at the condition of the keelbolts and check for any weeping or its associated ‘tea-stains’ around the fastenings which indicate water ingress.

  • Structural Checks: Lift the sole boards check for stress cracks and any detachment of items bonded in. Check the bulkheads bindings. They add rigidity to the hull and when the vessel flexes during a severe impact they can fracture and pull free.

  • Rudder Damage: Inspect the rudder for damage and look for signs of gelcoat crazing around the rudder fittings.

  • Rig Checks: The mast, rig and deck moulding will have been subjected to an enormous load if the vessel hit the bricks with full canvas. It is important that the mast and standing rigging is all thoroughly checked.


If anything looks suspect, get the boat out the water and have it looked at by professional boatyard.

With thanks to:
Salty John, specialising in a select collection of tried and tested sailing equipment - Web http://www.saltyjohn.co.uk/ phone +44 (0) 1995 672556 Fax: +44 (0) 1995 672425 e-mail: info@saltyj.co.uk
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