Striking Submerged Objects

Posted on by David Graham

Beware of SSO
SSO (Struck Submerged Object) and there is no-limit to what the object may turn out to be.  Yesterday we posted about a large shipping container seen floating off the coast of South Carolina.  Last week a fisherman spoke of a container floating off the coast of SW Florida. About 1400 containers fall of ships every year.  Most boaters hit things like: oyster beds, stumps, logs, submerged watercraft, shopping carts, refrigerators, crab traps, buoys, moorings, old pilings or pieces of docks.  Those are on normal days.  After storms the list is infinite what may be floating just below the surface in your favorite boating area.

Today, let’s review common areas these incidents happen…  What to do should this happen to you… And common damage you may find to your vessel, based on the propulsion of the vessel.


Areas to be most aware:
If you boat in shallow bodies of water, tidal shorelines, ports with construction, and in rivers or near mouths of rivers there is a high likelihood of floating or submerged debris. For most boaters it isn’t if you will hit an object, rather when.  Leading to what you should consider when you Strike a Submerged Object.

What to do:
1-When you feel  or hear it, slow the boat or stop the boat. Check to make sure you and your passengers are OK.


2-If you sense you may be in danger and don’t already have your life jackets on, instruct everyone on board to put the life jackets on.  Radio for help.


3-You and possibly others on the vessel should start checking different areas/bilges and compartments on the boat to see if water is coming in, look for smoke, smell for smoke, look off the back for fuel or an oil slick.  If you find water coming in, immediately try to slow or stop the flow of water.  Use rags or whatever is available to stuff areas that are leaking.  Radio for help!  You do have a marine VHF radio aboard, right?


4-If you are not aground, be aware of the surrounding for other dangers.  Restart the engines if possible and try shifting - Forward or Reverse to make sure you have propulsion.  If you are unable to navigate the boat and drifting toward danger, consider lowering the anchor.  Stay aware of your surroundings.


5-If you are able to navigate the vessel, cautiously accelerate and head toward the dock/safety.  Listen and watch for signs of damage. (Noises, smells, smoke or fuel slicks…) While the boat is moving along creating vibrations, those vibrations may cause something that wasn’t leaking to begin leaking.  Have a passenger or crew continue to check bilge compartments for water.


6-Following the strike, it is recommended that you have the vessel checked at the marina for any damage.  Depending on the size of the vessel or type of vessel, you can have it taken out and inspected it on the hard or have a diver come in and inspect it in the water for damage to the hull or propulsion system.  It is the responsibility of the boat owner to mitigate further losses and report any fuel spills to the authorities.  Check your insurance policy, as most policies provided by Charter Lakes offer coverage for: pollution liability and cleanup, collision with an SSO, towing, mechanical breakdown for a covered loss and any cost associated with inspecting the vessel for the cause of loss.


How to avoid SSO’s:
Submerged object losses can be very costly and keep your boat out of commission longer than you’d like, waiting for the marina to complete the repairs.  SSO’s may be floating and bobbing on the surface.  And like an iceberg the bulk of the object is below the surface. Sometimes it is just below the surface.  You and having someone else looking out, may help you avoid this type of collision. Listen to your radio, others may have seen objects floating in the water and announced it over the radio.  Be extra alert after storms as things blow in to the water or are carried into the water from high waters or tides.
Avoiding this debris through vigilance and preparedness as well as being a little lucky; can be the difference between a Good Day and a Tough Day on the water.


Damage based on type of boat:
A-Sailboats
Sailboats typically hit a submerged object with the leading edge of the keel and are typically going at a slower speed.  Start your search in the bilge near that section of the boat then look in other parts of the boat to make sure you are not taking on water or not taking in on quickly. 
B- Outboard Engines
Unlike with the sailboat strikes, outboard engine strikes typically occur at higher rates of speed. Often we find damage to the prop and prop shaft, possibly the lower gear unit. With this type of damage you may also have damage to the trim and even the transom.
Even the rope around a buoy or crab pot you hit, that can also cause damage to the prop and drive shaft, including overheating.
Outboards are a little easier to inspect and you will often feel vibration, trim the motor up and check the prop, if you have a spare, you may be able to change it and head back in.  Otherwise, you may be able to get back at a slow speed or rely on a second engine if you have multiple engines on your vessel. 
C- I/O powered boats
These boats will suffer similar damage as an outboard.  Often you will find water coming in through the gimbal bearing, stuff a rag in there to slow the flow.  Should you be able to limp back in at a slow rate it may minimize additional damage.  In other cases that lower unit could be ripped off the transom. 
D-Inboard Drives
These boats when striking an SSO often result in damage to the running gears; such as props, shafts, struts, transmission and rudders.  A severe strike may tear the shaft off the boat or drive a strut through the hull, resulting in water entering the boat.  Needless to say water entering the engine creates even more damage.
E- Pod drives Pod drives typically found on newer diesel vessels.  Pod drives are a combination of the I/O and the Inboard, only more expensive.  Damage from a strike will result in similar damage seen with an I/O or an Inboard.  These are designed to break away and “should not” allow water to enter the boat.

Stay safe and alert while out enjoying the water! 

Share this Blog with a friend of yours that also enjoys a relaxing day on the water.

Charter Lakes