There are a wide range of situations that would require you to refer to some kind of emergency survival checklist. You might be going out camping and you prefer a more primitive environment for your camping experiences which would lead to you wanting to avoid any luxuries other than what you have in the list. Alternatively you might be going to a different country where the political situation is a little unstable thereby requiring you to have some kind of list you can refer to in case you are forced to survive in emergency situations.
Most people talk about things like food when you are creating an emergency survival checklist that you will keep checking with to ensure that you have everything that you need, and while food is most definitely going to end up being important at this current point in time you should realize that while you can survive a week or so without food you probably won’t go more than two or three days without water. As a result of the fact that this is the case you should pack some water purification tablets that you can use to clean any water that you would find.
Packing water bottles is not going to be all that practical at all without a shadow of a doubt. Water bottles tend to be heavy, and it can be much easier for you to just find some water in a stream or a lake and purify it before drinking it. If the water is fresh you don’t have anything to worry about but there can sometimes be pathogens in said water so you should add the tablets to be safe.