Add a boat dock bumper to protect the piers from incoming boats. Dock bumpers are made of vinyl, rubber or high density foam, are easily available commercially and can be attached to your boat dock with a little effort. To start with, place the bumper alongside the pier and anchor it in place by screwing into the top third portion at level with the pier. Start with a single screw and gradually lift and attach the bumper along the full length of the pier, keeping a 6- to 12-inch gap between the screws. Once done, repeat the process by screwing into the bottom third of the bumper. Keep the screws in the two lines parallel to each other for a neat finish.