Even if you aren't going offshore, you should carry a ditch bag that you can grab quickly in case there's a problem. Ours is the kind used by sea kayakers to keep their gear dry, and we store it underneath the dodger when we're sailing so we can check the bag's contents and test the handheld VHF.
A quick-release buckle that wraps around a grabrail on the cabintop holds one end of the bag. A second line at the bag's opposite end also runs to a strongpoint; it's intended to be a tether that holds the bag to our raft. We've attached a folding knife on a lanyard to the bag in case we have to cut something quickly. We practice opening the knife with bare hands, with gloves on, and with our eyes shut to simulate darkness. Cary Deringer