The Open Boat: Why Did The Boat Sink?

There are many reasons why a boat may sink, from adverse weather conditions to human error. Some common reasons for sinking include a boat running aground or colliding with an object, bad weather, mechanical failure, or human error, such as poor maintenance or careless operation. In addition, factors like heavy rain, clogged scuppers, frozen hoses, and improper docking procedures can all contribute to a boat taking on water and eventually sinking.

Poor maintenance

• Lack of proper caulking or sealing, which can lead to leaks and water ingress. This is especially critical around scuppers, deck fittings, and through-hull fittings.
• Improper winterization, such as failing to close seacocks and drain plugs, or not using antifreeze, can lead to frozen pipes, cracked strainers, and other damage caused by expanding ice.
• Neglecting to regularly inspect and maintain hoses, clamps, and other plumbing components, which can lead to corrosion, cracking, and leaks.
• Inadequate battery maintenance, causing the bilge pump to fail and allowing water to accumulate.
• Failing to regularly visit and inspect the boat, especially during winter and early spring, when issues like leaks and battery problems are more likely to occur.
• Poor upkeep of the stuffing box or failure to use dripless shaft seals, which can lead to water seepage.
• Lack of proper maintenance of the transducer, bedding compound, and other components, leading to enlarged boltholes and water ingress.
• Not addressing issues with dissimilar metals below the waterline, which can lead to internal structural damage.
• Insufficient maintenance of the rub rail, allowing water ingress after impacts with pilings or other objects.
• Neglecting to drain mufflers or risers, leading to water accumulation and potential freezing and cracking.

Boat owners and managers have a responsibility to ensure proper maintenance and upkeep to prevent sinking and ensure the safety of the crew. Regular inspections, timely repairs, and proactive measures to protect against the elements are crucial to mitigate the risk of sinking due to poor maintenance.

Collision with another vessel

In some cases, a boat may be hit with such force that it capsizes, or rolls over completely, making it impossible to recover. This can happen due to the angle of the collision or if the boat is hit by a much larger vessel, such as a freighter.

Even a smaller collision can cause damage that leads to a vessel sinking. For instance, a boat's bolted-on swim platform could be loosened by a collision, causing bolts to weep, which could eventually lead to the boat taking on water and sinking.

In addition, vessels at sea are susceptible to collisions with semi-submerged containers, which can cause a sudden and catastrophic failure. This is especially dangerous at night or in low-visibility conditions when it is more difficult to spot these obstacles.

Furthermore, boats can also be struck by large animals such as whales, which can cause significant damage and even roll the vessel with the force of the impact.

Heavy weather

In addition, strong winds and rough seas can cause a boat to pound against a dock or other object, leading to a hole in the hull. Broken portlights and hatches are also more susceptible to damage in heavy weather, providing another entry point for water.

Furthermore, heavy rains and storms can cause scuppers to clog and decks to pool with water, weighing down the boat. If the scuppers become clogged with leaves, for example, the boat will take on more water, increasing the risk of sinking.

To prevent sinking in heavy weather, it is crucial to regularly inspect and maintain the boat's equipment, such as hoses, clamps, and bilge pumps. Properly securing the boat when not in use, using reinforced covers, and visiting the boat frequently can also help prevent water accumulation and structural damage caused by heavy weather conditions.

Human error

In addition, crew members themselves can be a factor. Crews that are understaffed or poorly trained may be unable to handle emergencies effectively. Crew fatigue, distraction, or substance impairment can also lead to mistakes that compromise the safety of the vessel.

Another human error that can cause boats to sink is related to docking procedures. For example, tying up a boat at low tide without considering the potential for the boat to become trapped under the dock as the tide rises. Or, failing to secure the boat properly during high tides, which can result in the vessel being held down by tight lines as the water level changes.

Furthermore, boat owners or managers who do not regularly visit and inspect their vessels can miss potential issues. For instance, leaks that go unnoticed and lead to gradual flooding, or failing to prepare the boat adequately for winter conditions, such as not closing seacocks or forgetting to winterize certain components, can lead to sinking.

In summary, human error plays a significant role in boat sinkings. Through proper training, maintenance, and adherence to safety procedures, many of these incidents can be avoided.

Mechanical failure

One common issue is the failure of hoses and clamps. Hoses can crack, especially around stress points created by clamps, and clamps themselves can give way, leading to water ingress. Regular maintenance and inspection of hoses are crucial to mitigate this risk. It is recommended to check hoses by flexing them and replace any that show signs of cracking. Additionally, securing hoses with two stainless steel clamps can provide extra security.

Another critical system is the bilge pump, which is responsible for removing water from the boat. If the bilge pump fails or the battery dies, water can accumulate and cause the boat to sink. Regular maintenance and monitoring of the bilge pump and battery are essential to prevent this issue.

Corrosion and deterioration of metal components are also significant concerns. Dissimilar metals below the waterline can cause each other to deteriorate, creating an internal structure similar to Swiss cheese. Sacrificial zincs and bonding of underwater fittings with a number 10-gauge green wire can help prevent this issue.

Other mechanical failures that can lead to sinking include:

• Rudder falling off
• Failure of the stern tube or stuffing box
• Engine problems
• Structural failure, such as a large crack or hole that cannot be easily patched

Frequently asked questions