I've taken some white caps aboard and the drain handled it with relative ease. Of course, you will want to keep the hatch closed. One of the benefits of owning a Montgomery is that they are well designed to be "dry" sailors. In rough weather I've usually taken more water up through the drain than spray from slapping waves or on a hard heel over the side. One trick I picked up from reading this mail box is to keep a large sponge wedged around the centerboard sheet under the transom. It effectively keeps the back flow under control and permits any cockpit water to escape. The 1000 MPH tape was a stutter - should have been 100 MPH tape. That's a clear very strong and very adhesive tape that will adhere to wet surfaces and hold its grip through "100 MPH". Its a great emergency patch (needs to be cut - can't be torn). I've kept a roll in the boat but have never had to use it after I fiber glassed the leak in my trunk. I'm sure it is long past its prime now. Found it in a Boater's World. I don't remember the brand name and it isn't written on the roll. Sorry. I'll see if I can find a fresh roll and will let you know. Check out Nor'Seas web site at http://www.montgomeryboats.com/ for some good pictures of Montgomery boats. Stan M-15, #177, Carol II