The River Walk
One day a group of tourist who had rented small sail boats and needed to cross the bridge to go to the other side of the river to get to the rental place. Other tourists had rented the huge party boats. The small sail boats were able to get through by going around by taking a small and narrow path of the river. The party boats were way to wide for that path so they had to take another way out. The big boats could only pass if they took a channel to the lock and key bridge. Once the party boats reach the lock and key bridge, one side contains more water than the other. The side that contains less water allows the party boat to go to it. Once the boat is in place, the water on the other side equals out and allows the boat to pass through. There for, the big boats can pass through the channel and are able to make it to the rental place on time!