Other than air (oxygen), nothing is more vital to life than water. So ask yourself some serious questions:
How quickly would you run out of water, if your water was unexpectedly cut-off for some reason? If you have your own well, assume the pump breaks for some reason and cannot be quickly replaced. Do you have enough stored water to last a week? Two weeks? A month? How much water do you actually need (btw, much more than the often given rubbish advice of 1 gallon per person per day). Do you know why you need more than 1 gallon per day? Do you know how and where to collect water? Do you know how to purify water?