Yes you can. Many ski packs are hydration compatible, allowing for a water tube to be housed in the harnesses and insulated from the cold. Inside the pack, there is space to store water bladders to which one can sip water using the tube from.
Hydration bladders are actually a better option than water bottles. Unlike, many water bottles, hydration bladders utilize less space and have incredible insulating abilities. Furthermore, they are in-destructible to the environment as opposed to purchased bottle water, because they are reusable. They are also very soft and yet sturdy that they don’t easily rip or break. And as an added value, they can even store hot liquids.