If you are planning to spend time on a sit-on-top kayak, it’s time to learn about scupper holes and scupper plugs.
Scupper holes are literally holes drilled all the way through your sit-on-top kayak. While holes drilled through a boat might seem unsafe, they are actually quite the opposite. These holes are actually safety features, allowing water to drain out of your kayak and keeping it afloat.
Sometimes in choppy water, these scupper holes allow water to go the wrong way, actually entering the boat, soaking the floor as well as the unlucky kayaker. To keep water from flowing into your kayak through the scupper holes, all you need to do is insert scupper plugs.
I have spent a lot of time on a sit-on-top kayak and have learned a few things about the nature of scupper plugs.
To use scupper plugs effectively, a kayaker must:
- Determine whether the water conditions warrant the use of scupper plugs,
- Figure out which scupper plugs will be most effective for the conditions and particular kayak,
- Insert the scupper plugs into the scupper holes,
- Prepare to remove water from the kayak manually,
- Remove the plugs before storing the boat.
Table of Contents
Do you need to use scupper plugs?
Each time you enter the water you have to decide whether or not to use scupper plugs (if you have a sit-on-top kayak).
Should I use scupper plugs if it is windy? If your trip is going to fall on a windy day, then expect to run into choppy water and waves. These might drive water up through the scupper holes and onto the floor of your kayak. This may be something that you want to avoid, particularly if, as with many sit-on-top kayaks, yours has holes placed right under the seat pad. Using scupper plugs in such conditions will help keep your legs and posterior a little drier. (If you like to kayak dry, I wrote an article about it here.)
Should I use scupper plugs if it is raining? If the weather conditions are expected to include rain, bear in mind that using scupper plugs will keep all of the water that falls from the sky in the bottom of your kayak. Because sit-on-top kayaks are open to the elements, they act like buckets when it rains. At some point – probably multiple times – you will likely need to stop paddling and manually remove water from the floor of your boat.
Also, using scupper plugs will reduce the safety of your kayak. If you accidentally capsize, then your boat will fill with water, making it difficult to re-enter and requiring time to manually bail out.
Should I use scupper plugs in perfect kayaking conditions? The main benefit of the scupper holes found in a sit-on-top kayak, is that they self-drain. This keeps your boat stable and safe – particularly if you lean a little too far and find yourself in the drink. The scupper holes will remove the water quickly, allowing you to re-enter a kayak that is still floating on top of the water.
To summarize, there is a trade-off between safety and comfort. To use scupper plugs is to stay a little drier on a windy day, but to risk a more significant problem if you are forced to re-enter a capsized kayak.
Which scupper plugs should you use?
Scupper plugs are little more than a glorified bathtub plug. They are small rubber or plastic pieces that you insert into the top of scupper holes to keep outside water from flowing back up into the boat. Use scupper plugs on cold, windy days when you don’t feel like sitting in a pool of wet for hours.
What are they made out of? Scupper plugs can be constructed out of several different materials, including rubber, plastic, EVA foam and silicon. They are typically 1-1.5 inches in diameter, and can be found in several designs that might take the shape of a bathtub plug, a tapered wine bottle cork, or even a fluorescent corkscrew.
Some kayakers even prefer to fashion their own DIY scupper plugs out of foam golf balls and a bit of cord. This fellow on YouTube fashioned some good ones here.
Get the fit right. When choosing scupper plugs, make sure you select ones that will fit snugly in your particular kayak’s holes. Sometimes this can be a frustrating trial-and error process because ‘one-size-fits-all’ might not be true. Fortunately, scupper plugs usually only cost $5-$10 per plug, so you can test a few without breaking the bank.
Make sure they’ll come out. You also need to be able to remove your scupper plugs. If you are on land, removing them usually isn’t difficult (unless they are too big for the holes). However, if you have just re-entered a kayak full of water, you want to be able to grip them and pull them out. Some plugs have cord attached that make them simple to remove. Also, plugs with cord are easier to remove if you are sitting in your seat and trying to reach the furthest ones (without tipping your boat over.)
Are self-draining scupper plugs worth the effort? There are commercial self-draining scupper plugs that can be purchased if so inclined. I have never used them and I have not heard much that is positive about them. However, there are some DIY self-draining scupper-fabrication videos on YouTube that appear to have proven successful. If you are handy (and obsess over scupper plugs), consider searching them out.
How do you actually use scupper plugs?
Scupper plugs are easy to use. Think about using them in the same way that you think about using your bath tub plug.
If you want to keep water from splashing up through the holes and into your boat, insert your scupper plugs. Position a plug over a hole and push down until it is firmly in place.
**PRO TIP: If you want to test whether your scupper plugs fit properly, insert them with your kayak in your yard. Then grab your hose and spray the inside of your kayak with water. Now look below your boat. If there are drips coming from your kayak, the scupper plugs either were not installed correctly, or don’t fit at all.**
Scupper plugs under your seat. One of the biggest complaints from sit-on-top kayak owners is about actually getting in the kayak. The problem is that the force of dropping into the kayak seat sends water up the scupper holes, immediately soaking the kayaker’s backside.
Many sit-on-top kayaks are designed with scupper holes directly below the seat pad. This can be a problem, particularly for heavier kayakers, because entry into their kayak produces a soaking wet bottom that lasts all day.
To avoid this, consider plugging only the scupper holes that are positioned directly below your seat. This will allow you to maintain a drier bottom while still keeping much of the self-bailing characteristic of scupper holes.
Alternatively, consider entering your kayak with the below-seat scupper plugs installed and remove them once you are situated in your boat. This will require some yoga-like positioning to reach and remove the plugs, but it is doable.
Stow unused scupper plugs in case you need them. If weather is expected to be dynamic, then stow the plugs in your kayak. You can simply attach them to the bungee cords located on your deck. If winds start to blow and waves begin to pick up, then stop paddling for a moment and install them.
Be prepared to manually remove water from your kayak
Water will always find a way into your kayak. If you choose to use scupper plugs in your sit-on-top kayak, you will eventually need to manually remove water.
Keep a kayak sponge on board. To clean up those small puddles slosh their way to your backside, use a kayak sponge and soak them up before they reach you.
Stow a bilge pump on board as well. If you are going to paddle with installed scupper plugs, then you must also carry a bilge pump. If your kayak capsizes, the only way you will be able to expel excess water is with a bilge pump. Simply insert the bottom of the bilge pump into the water, depress the pump handle, pull it back up again, and the pump will evacuate the excess water. Just make sure that the outflow hole is pointing over the top edge of the kayak.
Remove the scupper plugs before storing your kayak
When your kayaking adventure is over and it comes time to store your kayak, remember to remove the scupper plugs. Temperature changes can cause your kayak hull to expand and contract. If you store your kayak with the scupper plugs installed, the plugs could get stuck in the holes or worse, actually damage the hull – causing a dent or crack.
Don’t use the scupper holes to tote your kayak
The weakest points of a molded plastic kayak are around the seams. These seams are typically located around the edge of the kayak as well inside the scupper holes.
Some kayakers tote their kayaks with carts that insert solid poles through the scupper holes to hold the boat steady. Bad idea. Because the scupper hole area is fragile, allowing a metal pole to knock around inside it puts you on the fast track to a leaky boat.
Parting thoughts
Scupper plugs are easy to use. Simply push the plug in when you want to keep water out, and remove the plugs when you’re done.
When you use scupper plugs, you trade safety for comfort. Scupper holes are the mechanism that bails water from your kayak. If the water doesn’t bail through the holes, then you’ll eventually need to bail water yourself. As always, be thoughtful and exercise good judgement.