On my bike bivy's I take two water bottles (one full) so that when I pitch up I can collect enough water to last the evening and morning drinks & meals and the next day's ride.
I was restricted to just one bottle on my walking trip this week which meant I needed to make an extra water trip in the morning. On my way back to the car I realised I could have used a small dry bag to collect water and store it overnight.
Is there any reason why I can't start using a bottle and a dry bag, it would appear to make sense as it saves so much space... or am I being stupid somewhere?
What about a collapsible bag/ bottle - platypus do one, or even empty camelbak type bladder? Take minimal space empty but fill up and food/ drink grade material.
Sounds perfectly fine (but try it at home in case it tastes rank!)... But why not carry a decent sized ziploc bag for the same purpose? Lighter and designed for food/drink. Even works fine as a dry bag for your warm jacket or similar too.
I've done exactly that before now. Got to a Bothy. Unpacked and set up sleep kit. Turn dry bag the sleeping bag was in inside out and fill it up.
That was in my running days, most of my bags tend to be very muddy now! I do use a 0.75-2.0litre 'water bag' like the ones that come with sawyer filters. They roll up very small
A few companies used (might still) to produce a silnylon water bag. I recall they weighed less than 20g but could hold a gallon.
Like others, I often carry a 2l platypuss soft bottle which I fill up for the night shift ... probably much easier to pour from than a material bag and there's the added benefit that you can screw a filter on if you like.