Scupper holes

Scupper holes are vertical channels molded straight through the hull of a sit-on-top kayak, connecting the top of the deck to the water below. Because the paddler's seating area is above the waterline, any water that washes onto the deck from spray, waves, or dripping gear simply runs down through these holes and back out, rather than collecting around your legs and feet the way it would in an open sit-inside cockpit.

Most sit-on-tops have several scupper holes positioned near the seat, the footwells, and sometimes the tank well at the stern, and the exact count and placement varies by model and hull design. In calm, light conditions scupper holes can occasionally let a small amount of water spray back up into the boat, which is normal and drains straight back out.

Scupper plugs are removable inserts that block individual holes when you want a drier ride in calm water, and pulling them again when conditions pick up or when the boat is loaded heavier, since a loaded hull sits lower and drains more effectively with the holes open. A common mistake is plugging every scupper hole and forgetting to remove the plugs before launching into rougher water, which defeats the self-draining design entirely.