Going to the beach on my period

Vvl
I got my period today, and tomorrow I am going to the beach. The thing is that is on a boat with no restroom. I have a heavy flow and I am scared because if I use a tampon I may have to use it more than 8 hours. I wont be able to change it because there is no restrooms. What do you recommend me to do? I was thinking in not going but I really want to go!!
Thanks!