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Bottoms Up - What To Do If You Run Aground

The Fraser River Delta, just west of the Vancouver Airport (YVR), is extremely shallow. I knew that, but when you are running two miles off shore in a high speed boat that only draws 10 inches of water, it is easy to forget. One sunny day we were motoring south past the airport in my twin powered Shadow Cat and cooking along to get to a marina on the south side of Point Roberts, USA. As we flashed by a stopped cruiser I noticed a man standing on his rear deck and watching us closely. I recall thinking that he was parked in an unusual spot. Three seconds later I did a face plant into the steering wheel as our boat ground to an immediate stop. We were hard on the bottom. Looking back we watched the man in the boat we passed, step into the water and walk towards us. The water was just over his ankles.

Most boaters will have a grounding experience at least once. If you boat in Florida, it will be more. People say that there are two kinds of Florida boaters -- those who tell you they have run aground -- and those that lie. Wherever you boat, it is wise to understand what to do when it happens to you. For that time when the bottom comes up to greet your boat, here is the basic protocol to follow. Not every step will apply to your specific situation.


What did you hear? If the bottom is soft, you will first feel the motor slow for a second or two as the prop slices into the bottom. You may have time to recover if you immediately trim up. If you hit a rock or a floating object, you will hear a sharp impact. In either case, quickly trim your drive to full up and move the throttle to neutral. Once your boat has stopped your first concern is the status of your passengers. Most groundings do not result in personal injury, but passengers might require attention when an abrupt stop jolts them into a hard boat part.


Checking for boat damage is your second move. For sterndrive and outboard boats, inspect your prop and drive. You may be surprised to see no visible damage. If this is the case, you can turn your attention to getting free. If your boat is an inboard you can plan for the worst. Even a mud bottom can bend a shaft strut or propeller blade. You will have to dive under the boat to determine your chances of motoring off. In the case of visible damage on any boat, your next move is to prevent further damage. Call for help, or if your boat is a twin, attempt to use only the good engine/drive to move free.


If your grounding is in tidal waters, you have about a 50% chance of joy.


An incoming tide should soon give you the depth you need to motor off, but an outgoing tide will make matters worse as time passes. Lets say you have no tides. In this case, trim your drive to it's highest point where water can still flow through the motor and you can see water exiting. Many times it is only your drive that struck bottom and by using a maximum trim height, and a little rocking to and fro, with the prop barely in the water, you can slowly motor off. Whether you go forward or backwards will depend upon your read of the depth fore and aft. Obviously you want to take the shortest route.

If you cannot power off, your next move is to trim full up and attempt to float the boat. Moving all passengers to the bow can often raise the stern enough for the prop to turn freely. When that fails, moving people out of the boat is required. While you will likely be in very shallow water, be careful that the bottom is not ultra soft mud that could result in passengers getting stuck, along with the boat. Usually a couple of volunteer jumpers is sufficient to allow the boat to float, and then all that is needed is for them to walk the boat to deeper water.


If your boat is a cruiser, you can remove more weight by launching the dingy and loading heavy items into it, such as anchors, coolers, bait tanks and any complaining passengers. Heavy water tanks can easily be emptied. If you think you are aground on a short reef you can also try "kedging." This is a process whereby you walk the anchor forward 10 or more yards and set it. With one person pulling the anchor and the remainder pushing the boat, even heavy cruisers can often be unglued.


Calling for commercial assistance is expensive and even they will begin by trying the above steps. When you do remove your boat from a grounding, be sure to flush your motor in clean water to help prevent water pump damage or water flow blockage. As you continue your cruise, a rough vibration is a sure indicator that damage has occurred. Examine your propeller closely. Even a tiny nick will greatly affect performance so gently file out any small scratches and test again for vibration. Stainless props will survive a hit much better than aluminum and stainless props can be repaired. When you send an aluminum prop in for repair, the heating necessary to hammer it back to the correct shape on a "pitch block" changes the molecular structure and while it may look great, it will be much weaker.


When you return home, it is recommended that you write up a record of the event, because your motor may have suffered gear damage that only shows up weeks later. If this happens you will need to show your insurance company the when, where, what, plus passenger witnesses for the grounding event. Of course, the ultimate grounding cure is to know the water where you intend to boat and if you are not sure you are safe, adjust trim and weight distribution to reduce risk.


So what happened to us when we found ourselves aground off Vancouver? Well, we were lucky. Following the above steps, our stainless cleaver props were undamaged and the tide was coming in. All it took was a high trim angle and we were able to proceed at a slow idle until we were clear of the mud flats. #tips #quicktips

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