Keeping Your Boat Afloat

An analysis of a year's worth of sinking files reveals the 10 most common reasons that boats end up under the water.

By Beth Leonard
Published: April 2014

Chart: Causes of boat sinkings

As the pie chart shows, more than two-thirds of the reasons why boats sank could be considered preventable. Half of those preventable claims, or one-third of the total, involved boats that sank due to the gradual failure of a part below the waterline. This is the single most common reason boats sink at the dock. While failed parts also cause sinkings underway, it's much more common that they result from the boat hitting something, whether another boat, the bottom, or something floating in the water. Failing to secure an otherwise working fitting, such as a drain plug or a sea strainer, when the boat is in the water comes third on the list.

Chart: Locations of Boat Sinkings

One big change we have seen is that swamping, responsible for eight percent of the sinkings in our files, is much less likely to occur underway than it was in 2006 when we last looked at our sinking claims. The low-cut transoms that were so common in the 1990s have largely been replaced by splashwells separated from the interior of the boat by a high transom. This time around, only one boat sank as a result of a wave swamping the boat from astern. Instead, boats were swamped at the dock when tied stern to open water in chop or waves raised by strong winds. Finally, as was the case in 2006, five percent of the boats that sank got caught under the dock by waves or tide due to problems with their dock line arrangements.

You can greatly reduce the chances of your boat sinking due to wear, tear, and corrosion by adhering to a regular maintenance schedule. While all maintenance is important, the first six items in the list below represent the most common maintenance-related failures that led to sinking in our claim files. The additional four items in the list could be considered good seamanship, and will help to prevent boats from sinking due to causes other than age and deterioration.

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