you might be seriously thirsty on many stretches of the route with one water bottle. It will also depend on the weather, if its warm, bring more. I can't remember what I had last year, I think two water bottles and the camelbak - 70oz - but maybe I skipped the camelbak and put additional bottles in the rear seatpost rack, many of these rides blend together! I was pleasantly surprized with the amount of options along the way to refuel. This year I will be using my full susser, so no rear rack. So, two bottles and maybe the 100oz camel. Done!