L.J.
We do the beach/river with a group of boating friends every Sunday afternoon with friends. We all have various bags, etc. But the one bag that we all have is... the XXL Ziploc bags. They are great for the beach, boat, whatever. They have handles and are heavy duty too. I use the same one pretty much all summer. I usually put the food in one because it wont get wet and the bags seal up just like a ziploc so you can keep sand and moisture out. Depending on which boat we take, I'll put the towels in one also so if the current is rough they don't get wet. You can get them at the grocery store and use a coupon (I'm all about that!) I think one box usually has 3 bags in them. I also have an LL Bean boat bag which I love but it's not waterproof and is hard to keep clean.