Cockpit Drains and Scuppers

Keeping the Boat Dry with Cockpit Drains and Scuppers

One cannot escape the marine fact that ships take on water. Whether from ocean spray, rain, wet things and people, water gets onto the deck. Most of the time it can be sluiced off easily, but in the cockpit this water tends to puddle without proper drainage. In these cases, a properly installed scupper and cockpit drain can help redirect that water back into the ocean where it belongs.

Cockpit Drain

A ship’s cockpit can be the section where a sailor mans a tiller to steer the boat or in larger motorized boats, the place where a ship’s electronic controls are located. Like many parts of a boat, the floors of these cockpits can quickly gather puddles which can be dangerous to both individuals and equipment, requiring the deck to be swept clean or, in extreme situations, bailed out. This requires drains to be installed in the floors of these cockpits, allowing a helmsman to concentrate on steering the boat and not on gathering water. Cockpit drains allow for water to flow through to pipes that run under the deck and out to waiting scuppers that usher the water out to sea.


A scupper is the outside component of small drain that redirects water from the cockpit drainage pipe and out through the side shell of the boat. They are “non-return” drains because they are one way; water leaves the ship and won’t come back through the pipe and back up into the cockpit. These scuppers are specially designed to block wave swells and other outside water from entering the drainage pipes while still allowing water to flow out. Without reliable scuppers to block the water, it can reenter a boat’s drainage holes, flooding a cockpit from the outside in.

Scupper Designs

Scuppers can be self bailing or use valves to help water move one way and out of the cockpit of a ship. Self bailing scuppers may be a self contained cone-shaped mount through which water flows down to a pipe. This design uses a plastic ball that floats up with the outside water’s level and blocks the water from entering the pipes. In this way it is self sealing. Scupper valves use a flap on the outside drain that uses wave pressure to keep it from opening easily.


The cockpit drain should always be kept clear of debris. This means clear of debris at the drainage opening, through the pipe, and at its outside opening. Failure to keep it clean can cause water to back up the pipe and flood the cockpit, possibly damaging sensitive and expensive electronic equipment or storage. Boat owners should always sweep the drain opening clear whenever any debris gathers near or around it; this small cleaning will stave off larger clogs in the future. Also, owners should consider having the pipes professionally swept once a year to get rid of any buildup. Finally, the outside port should always be monitored. Anything that catches on the scupper or around the drain should be removed.

Boat strainers are a good way to keep the drain and scupper clear of debris.

With proper installation and maintenance, cockpit drains and scuppers can work together seamlessly to keep a cockpit dry and safe, letting helmsmen and women to concentrate on navigation and safe boating techniques.