In a survival situation, usually shelter, then water and finally food – in that order of importance is your priority.
But, of course it all depends on the circumstances you find yourself. Either way, you can’t live very long without water. You need fluids to keep going, to replace what you lose sweating and through normal biological functions. Given a normal, healthy adult you can live three days with no fluid intake… give or take a day or so. If you have never heard of the “Rule of Threes” then think of it like this. You can live 3 minutes without air, three days without water and three weeks without food.
In a cold, damp, snowy environment you will be inundated with cold. You probably have about three hours to live without shelter.
Of course, remember that this is a rule of thumb, not an absolute.
Regardless you will need to locate and purify water to be able to drink it in a very bad situation.
Here we will place links to various sites and articles about locating, cleaning and purifying drinking water. As always, read and throw out anything that sounds “wrong”. Use your common sense. If you ever find yourself in a situation where you need to find water, you will at least have a working knowledge of how to locate water. Also, as always comments are welcome and place any links you believe are good in the comments and they will be added to the text of this page.