You may have noticed that your kayak has holes and wondered why.
After all, if you’re in a vessel on the water, it seems counterproductive for the vessel to have holes in it.
Quite on the contrary, there is a number of good reasons why kayaks plug holes are useful, so let me explain.
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What Are Kayak Plug Holes?
Plug holes, or scupper holes, are small holes in the bottom of sit-on-top kayaks. They are arranged to improve the buoyancy of the kayak by draining water that enters it.
With a sit-on-top, you sit open on the kayak and not in a closed cockpit as usual. This means that splashing water gets into the kayak more easily. As the kayak is slowly filled with water, it loses its flotation which makes it harder to maintain balance and continue paddling.
That’s where kayak plug holes come in handy. You can relax and enjoy paddling without having to worry about draining the water with sponges or other mechanical means.
Why Does My Kayak Need Plug Holes?
Drainage holes are for safety, to allow water to drain out of the kayak from the top down, and prevent you from sitting in a puddle. But which types of kayaks need to have them?
Sit-on-top (ocean kayaks)
This type of kayak originated in sea kayaking. It has a more stable construction with a flatter bottom so that the kayak wouldn’t sink in higher waves.
Yet, this flat shape requires an efficient way of letting the water in and out of the kayak without sinking. This is why SOT kayaks will always have kayak plug holes.
Sit-in kayaks
Sit-in kayaks allow you to sit at water level and inside the boat. Splash skirts prevent water from splashing into the kayak, Should water still leak inside, it can be drained via a drain plug at the stern – but only once you’re back on land.
In a sit-in kayak, the kayaker doesn’t have easy access to the inside of the kayak, so you’ll be sitting in a puddle of water every now and then.
However, a sit-in usually has a rounder bottom to reduce drag, so it’s still easier to paddle even when it’s filled with water.
Fishing Kayak
There is no specifically designed fishing kayak, but the sit-on-top (or SOT) kayak is most commonly used. Depending on the season and duration of your outing, it can be very unpleasant to have water in the kayak – not because of the risk of sinking, but for comfort reasons.
However, fishing usually takes place in calmer waters, so it is very unlikely that water will enter the SOT while you are calmly waiting for the fish to bite. But who knows, sometimes it may get slightly more adventurous than you expected.
Should Scupper Plugs Be In or Out?
First, let’s start by reviewing what scupper plugs even are, and what their purpose is.
What are Scupper Plugs?
Scupper plugs are small rubber or plastic pieces that fit into the scupper holes of a kayak and block or cover the drain holes. This prevents the kayak from draining itself.
Now, you may be asking yourself – why put holes in a kayak if you need to seal them shut anyway?
Scupper holes come with these purpose-built scupper plugs for the times where the drain holes are a problem rather than a solution.
Since in sit-on kayaks the deck is much closer to the water surface. This could let water enter the cockpit through the drainage holes, for example in high waters.
The purpose of a scupper plug (or short, scupper) that fits into the drain holes is to keep water out of the cockpit. This can happen in rough seas or when the hull of the kayak is pushed deep enough into the water to force water into the cockpit.
Plugging the holes will help your kayak maintain its stability and balance.
So Should the Scupper Plugs Be In or Out?
Scupper plugs that cover scupper holes can be helpful in a variety of situations. Think about paddling in rough water; the constant flow of water can affect the natural buoyancy of your kayak, necessitating the use of scupper plugs.
Moreover, if you are paddling with a large load, you should put the scuppers in before paddling, as the extra weight will dig your kayak in deeper and the water will rise out of the holes.
It is ultimately your decision whether or not to plug the scupper holes, although the plugs are really useful. You can paddle on smooth water and not need plugs, or you can paddle on rougher water and need them.
Read our 12-Step Guide to Becoming a Water-Conscious Traveler
Types of Scupper Plugs
The best type of plug, of course, is the one that seals tightly and stays in place. By design, they fit a specific hole size and are suitable for a narrow range of applications.
Material
Rubber and rope: The simplest there is – solid rubber stoppers with a conical shape. You press them into the drain hole or remove them by tugging at the attached thin string. The downside is that their quality will degrade over time due to exposure to sun and water. One-size-fits-all plugs also don’t ensure a very tight seal, might fall out, or allow for leakage. Tka
Molded nylon: These can come with a special gasket that you adhere to the scupper hole, and then screw the plug into the sleeve – not directly into the hull. Normally, once you screw the gaskets into the kayak body, you can always buy replacement plugs. Use a sealant such as silicone for a 100% waterproof plug.
Design
Press-in: Universal, fit most SOT kayaks, are easy to find, and affordable.
Screw-in: Some plugs are screw-on to ensure a watertight fit. Due to the sealant used to glue the gasket into the kayak hole, and the rubber insulation ring on the plug itself, this type is super waterproof.
Functionality
Self-draining: They prevent water from rising through the scupper holes, while still allowing splash water to drain out freely.
Pull loop: A traditional design with a heavy-duty rope pull that you can remove easily without special tools. The ropes do not protrude as high as cast-in pull loops, making the deck more comfortable to walk on while fishing or paddling.
Shop for scupper plugs online or at your local outdoor store.
Difference between Scupper Plugs and Drain Plugs
When shopping for kayak plugs, make sure you are purchasing the correct ones. The difference here is mostly in the type of kayak you own.
If you have a sit-in kayak, you probably have a drain plug. Just like in a boat, water that accumulates during a day on the water needs to be removed after use. Usually, there is a drain plug on the bottom of the kayak at the lowest point to allow the water to drain out once you get back on land.
On the other hand, with a sit-on-top kayak, the water drains out of the boat by itself continually. This is a thoughtful design because it prevents water from accumulating too much. As opposed to the drain plug, the overflow plugs will drain themselves continually while you are still paddling.
So there you have it. A drain plug and a scupper plug perform the same basic tasks, but on two very different kayak designs.
Will My Kayak Sink Without Scupper Plugs?
In calm water, no sit-on-top kayak will sink if the holes are not plugged. In rougher water, a kayak may begin taking on more water than necessary if the holes are not plugged. If anything this may cause some discomfort to the kayaker in colder conditions.
The question of whether you absolutely need to or not can be answered definitively with: It depends.
If you don’t mind sitting in water or are paddling in breaking waves, you can leave them out. It may even be quite refreshing in the summer, but maybe not in the winter. Scupper plugs are a good choice if you are paddling in calm waters and want a dry place to sit.
In any case, it’s not a good idea to completely plug the scupper holes. This could cause your kayak to flood and become too heavy to paddle with no way to quickly drain it. It’s probably best to have well-fitting scuppers at hand and to attach or remove them as needed.
You can even leave an opening or two open to achieve an ideal balance between draining and keeping the deck dry.
Final Thoughts
Kayaking is becoming more and more popular with the rise of ecotourism and slow travel. It’s a great way to enjoy the sight of nature undisturbed and without any harmful emissions.
But kayaking can also be a nice endurance sport that trains the whole body. You can have a proper adventure or just let yourself be guided by the course of the river or lake you are in.
Either way, whether you already own a kayak or you’re about to take your first paddling trip – now you know what those kayak plug holes are for.
There is even more you can do to become a more reponsible traveller!
Mike Blair
Sunday 16th of July 2023
I have a Marvel 14.5 ft tandem "sit-in" kayak. My drain plug is in the center of my kayak near the top. Do I leave it un-plugged or plugged in during kayaking. They aren't scuppers, it's one drain plug.