The apocalypse water will last for around seven days before the water becomes contaminated.
After seven days, the sewers will overflow and drinkable water and waste water will mix and cross-contaminate.
According to one new estimate, everyone would be dead in less than a year.
Physics students at Leicester University calculated that in as little as 100 days, humans would be outnumbered a million-to-one if an infectious "zombie virus" were to strike.
How long will gas last in Apocalypse?
There are technically fuel stabilizers that might help it last a little longer, and if stored in a proper fuel container with a fuel stabilizer the gas could last anywhere from 6 to 8 months.
But most claim that after a year this fuel is unusable.
How much water do I need in an apocalypse?
The Center for Disease Control says that a three-day supply should be kept on-hand at all times but suggests keeping two weeks' worth of water.
Three days of water for a family of five is 15 gallons, while two weeks' worth of water is 70 gallons.
If you have plastic during the apocalypse and wood to burn, you can create a distillation process that will generate water.
If you don't have wood to burn or you don't know how to start a fire, but you have a bowl, a cup, and it's sunny, you can let the sun do the work.
In general, you can survive without drinking water for up to 3 days.
But there are claims that they have survived 8 to 10 days, even a drop of any fluid.
You can stretch the amount of time to survive depending on external factors.
Examples of these are humidity, temperature, and general health.
As a general rule of thumb, a person can survive without water for about 3 days.
However, some factors, such as how much water an individual body needs, and how it uses water, can affect this.