You can use a long piece of thread during white water rafting as a safety line. Sure it's thin, but if someone goes overboard even a line of thread is better than nothing. Throw them a line and drag them back aboard!

The person who threw you that line of thread is actually a centaur (せん). How kind of him. After you are safe you hop on the centaur's back and ride around to get the wind to dry you off.