Build a raft out of plastic containers
Anyone who has seen the movie Jaws knows that plastic containers make great flotation devices. So, it’s a given that they can be used to build a raft. All that’s needed are storage bins and plywood. This DIY project may be a bit complex, but it’s worth the effort.
Use the plywood to make a frame and screw the containers onto each square of wood. Make sure that there are no gaps through which water could get in. Then, it is just a matter of covering the tops with planks. For more information, look up online a more extensive tutorial.