What Is a Scupper Hole and What Does the Plug Do?

Who would have guessed that those holes in the bed of your kayak are actually a safety feature that can save you from sinking or even drowning in deep water?

You may be wondering why your sit-on-top kayak needs four additional holes on the bottom; “Aren’t these holes simply for aesthetics?”

“What is the difference between a scupper hole and a scupper plug? Do you actually need them?”

We thought these questions might be roaming around in your head, so that’s why we’re here to answer them!

What Are Scupper Holes in a Kayak?

Scupper holes are present in the bottom of most sit-on-top kayaks. The kayak’s engineers include bulkheads in the kayak’s hull to allow water to drain through them, preventing you from sinking. 

They’re mounted on the sides of your boat and, aside from looking cool, kayak scupper holes serve a vital purpose. A kayak’s scupper holes are located at the lowest points of the boat, so you will usually find two in the front and two on the back.

Any excess water that enters your boat from paddle splashes or large waves will drain out of these scupper holes, allowing you to keep yourself above water. They force water to leave the boat and eliminate the need for you to bring extra equipment, like a bilge pump.

What Is a Scupper Plug and When Should You Use It?

If your kayak features scupper holes, you’ll need to know how to use scupper plugs. You will want to insert these to plug scupper holes anytime you beach, move, or store your kayak. 

You can also use scupper plugs while on the water if it seems like more water is getting in through these holes than out. Blocking the water’s entry point is especially useful if you’re paddling on cold water and you can feel it splashing up through the holes. 

The majority of scupper plugs you will find are made of plastic or rubber. Their function is blocking water from getting into places it doesn’t belong and offering you a drier ride.

There are several areas in a kayak where water pools, so you’ll need to use plug holes to direct the water more efficiently.

When shopping for plugs, some people wonder: Are scupper plugs universal?

A universal plug can be purchased from a variety of online and local retailers that sell equipment for sit-on-top kayaks. Cone shaped universal scupper plugs will fit in most kayaks.

To ensure a water-tight fit, some plugs have a screw-in design. It is very easy to install scupper plugs; it simply involves either screwing or pushing the plug into the hole. 

Some people create their own DIY scupper plugs with foam practice golf balls or other squishy materials that can fill the holes. Making your own scupper plugs is a fun way to customize your kayak.

Scupper valves are a more expensive kind of plug that has a dual function. Scupper valves are designed to let water drain out from the boat but not let any splash back up inside. 

If your normal conditions for kayaking are bodies of flat water, these valves aren’t necessary; but they can be handy for those who kayak on rougher waters.

How Do Scupper Holes and Plugs Work?

Before you put your kayak on the water, remove the plugs and leave the scupper holes open to drain water. It may seem counterintuitive to leave holes in the bottom of your boat, but trust that the kayak designers know what they’re doing!

Leaving the holes open, especially when you’re on choppy water, gets rid of excess water that splashes into and accumulates in the bottom of your kayak. This prevents the water from building up and weighing down your kayak. 

Scupper Plugs Help You Stay Safe When Kayaking!

Knowing when and how to use the scupper holes is crucial for your kayaking travels. Their self-bailing feature makes your journey much easier since you don’t have to repeatedly stop to bail out water yourself. 

When you kayak, you will end up with a bit of water in the bottom of your boat no matter how careful you are. Those who enjoy kayak fishing will usually get even more water in their boats. 

When you’re using a sit-on-top kayak, you won’t have a lot of extra storage space. Self-bailing holes prevent you from having to bring extra equipment like a sponge or bilge pump to deal with the water.

So if these holes are so efficient, do you even need scupper plugs? The answer is really a personal choice, but many feel that scupper plugs are worth the small investment. 

You need scupper plugs to be prepared for any water and weather conditions you might find yourself in. If you’re floating down a cold river and find that icy water is entering the boat through the scupper holes and freezing your toes, you’ll probably be looking around for your plugs!

How to Tell if You Need Kayak Drain Plugs or Kayak Scupper Plugs?

Drain plugs are primarily present in sit-in kayaks. You can remove all the accumulated water from the bottom of a sit-in kayak using a drain plug after a day on the water.

Similarly, but with a few key differences, scupper plugs are found in sit-on-top kayaks. Even though they sound the same, scupper plugs are different from drain plugs because they perform two different functions.

A scupper holes in sit-on kayaks are often smaller than drain holes and need to let water in the boat drain out while keeping the water underneath the boat from getting in. Drain holes are only used when you need to empty boats or sit-inside kayaks.

So scupper plugs are often not used while you’re out on the water in a sit-on-top kayak. But drain plugs should always be used while you’re on the water in a sit-inside kayak because too much water can enter the boat through the drain hole if the plug isn’t inserted.

Can you use a kayak without a scupper plug?

Rest assured, scupper plugs are not absolutely necessary. Especially in the summer, when you don’t mind a little splashing water, or if you come prepared with a dry suit in the winter!

Scupper plugs are beneficial for beginner kayakers who may be uncomfortable with leaving the scupper holes open. However, scupper plugs are not necessary and the kayak can function well without them in almost all conditions.

Scupper plugs can only be used with a sit-on-top kayak that has scupper holes. So, if your kayak doesn’t have any scupper holes, no worries — you won’t need a scupper plug.