I would get rid of the camelback, you will almost never need more than 3 bottles. If you do need more, just buy what you need in a convenience store - a couple of 1-liter bottles or whatever - put them in the trailer, and then recycle/discard the bottles when you are past the dry patch.
The camelback is extra weight that doesn't serve a function, unless you are wanting to use it as a little day pack for hiking. The whole just-in-case mindset needs to be examined carefully every time it comes up, because if you just-in-case everything the bike gets so heavy it's not fun to ride anymore.
My $.02, FWIW, YMMV, etc etc