I have had a Spyderco knife that has miraculously endured 13 years of salty sea kayaking in my life jacket pocket with just a quick rinse after every (most) paddles. It flips out easily with one hand so you can keep your other hand on the paddle. Well worth whatever I payed for it back then.
For multi-day excursions I keep a leatherman in a dry sack. The number of times it has gotten me out of a jam is too much to mention. With a combination of a Leatherman, duct tape and marine goop tp waterproof the tape, there is very little you can't fix.
I'm Riffing. People usually stop me when I'm riffing. Or carry on without me. That's also an option.