I agree with everyone: patience and persistence gets another vote.
You have to wait an hour. So? It will take as long as it takes, there's nothing wrong with that and nothing you can do about it. Put all thought of time out of your head, and if you only have a limited time frame, chose another day to tackle water crossing. Sure, the other riders had to wait on you, so maybe go out with a smaller group of close friends that will help or at least be willing to wait without you feeling like you're wasting everyone's time.
The most important thing is, as with anything else, is to never, ever give up. If it takes 6 hours or 20 minutes, don't give up or you lose and the fight will be that much bigger the next time.
I put pressure on them when they want to turn away or go away, and let them relax when they're standing near or facing the water. Then begin to put more pressure on them. Pressure and release, and wait them out. Pressure and release works for most everything. As long as you don't make a big, scary, stressful deal out of it, the more you do it, the easier it should become. I also agree with Jacksmama-spend time in the water and crossing the water, letting him get used to it. Again, the more you do it, the easier it should become.
As you discovered, getting off and leading is probably not the best idea. It's far too easy for a horse to jump on you or drag you and for you to get hurt. And a bribe (kind of) worked, but remember that you won't always have food, and eventually your horse is going to need to learn to go because you told him to, not because he's in the mood for a treat.