When a horse does not want to go to an area, work the horse near where you want the horse to go and only allow the horse to rest when it gets closer to the disliked area. For example, if your horse does not want to step in water, forget the water and work serpentines or circles at the trot if possible near the water. As the horse begins to focus on you, work it a little closer and let it rest as it makes it closer to the area. If it steps into the water, stop and rest. In no time, the horse will be willing to go ahead.
This is the same for a horse that refuses to move forward for any reason. Work in many directions in serpentines, circles, and figure eights, and let the straight-ahead movement be the reward. Make the thing that you want the horse to do easy. Make the thing you don't want the horse to do hard.
