# How Long Does Water Stay Fresh? **URL:** \ **Category:** Factual Questions\ **Created:** [September 16, 2005, 7:04pm UTC](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020 "2005-09-16T19:04:04Z")\ **Posts on this page:** 7\ **Page:** 2
**Author:** ![wevets](https://avatars.discourse-cdn.com/v4/letter/w/e9a140/32.png) [@wevets](https://boards.straightdope.com/u/wevets)\ **Post date:** [September 17, 2005, 4:20am UTC](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020/21 "2005-09-17T04:20:55Z")
> [@Leaffan](#): > > That’s impossible. It _ **IS** _ H20 after all. It can’t possibly loose oxygen and remain “water.” I think s/he means _dissolved_ oxygen, which is lost to the respiration of bacteria and other microorganisms even in a completely enclosed container. Also, autoclaves not only sterilize material by increasing temperature, but also by increasing the pressure. ---
**Author:** ![Eleusis](https://avatars.discourse-cdn.com/v4/letter/e/f4b2a3/32.png) [@Eleusis](https://boards.straightdope.com/u/Eleusis)\ **Post date:** [September 17, 2005, 11:32am UTC](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020/22 "2005-09-17T11:32:20Z")
If your water has enough _shit_ in it to grow harmful bacteria to a dangerous point, it probably wasn’t safe to drink in the first place. ---
**Author:** ![guizot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/guizot/32/3636_2.png) [@guizot](https://boards.straightdope.com/u/guizot)\ **Post date:** [September 17, 2005, 3:55pm UTC](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020/23 "2005-09-17T15:55:53Z")
Here in the earthquake zone we keep on hand four gallons of water per person, but we renew it every year or so because they say the plastic of the containers can affect the water over time, giving it a bad taste. ---
**Author:** ![TimeWinder](https://avatars.discourse-cdn.com/v4/letter/t/bcef8e/32.png) [@TimeWinder](https://boards.straightdope.com/u/TimeWinder)\ **Post date:** [September 17, 2005, 6:04pm UTC](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020/24 "2005-09-17T18:04:23Z")
Not what the OP asked, but most big drugstores will also have a variety of tablets that can be dropped into water and will sterilize it (or at least make it drinkable). Very small quantities of bleach have the same effect. These treatments are meant for microorganisms; they won’t clean lead or mercury out of water, for example, but it’s the microorganisms you probably care about in an emergency. I’d stick a few packs of these tablets or a jug of bleach (check to make sure it says it can be used for water purification, some have additives) next to my water stores, and not worry about bacterial growth. Don’t drink the bleach by mistake. ---
**Author:** ![picunurse](https://avatars.discourse-cdn.com/v4/letter/p/7bcc69/32.png) [@picunurse](https://boards.straightdope.com/u/picunurse)\ **Post date:** [September 17, 2005, 11:48pm UTC](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020/25 "2005-09-17T23:48:04Z")
> [@Eleusis](#): > > If your water has enough _shit_ in it to grow harmful bacteria to a dangerous point, it probably wasn’t safe to drink in the first place. Please re-read post #19. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [September 19, 2005, 11:43am UTC](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020/26 "2005-09-19T11:43:43Z")
> [@](#): > > Simply bring water to boil raises its temperature to 100°C and that does not kill enough stuff. An autoclave is like a pressure cooker and allows higher temperatures. An autoclave will go up to 121°C and that is hot enough to kill almost anything. You obviousl;y didn’t read the links I posted. ---
**Author:** ![drachillix](https://avatars.discourse-cdn.com/v4/letter/d/48db29/32.png) [@drachillix](https://boards.straightdope.com/u/drachillix)\ **Post date:** [September 19, 2005, 3:36pm UTC](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020/27 "2005-09-19T15:36:57Z")
> [@TimeWinder](#): > > Not what the OP asked, but most big drugstores will also have a variety of tablets that can be dropped into water and will sterilize it (or at least make it drinkable). sodium metabisulphite AKA campden tablets. Homebrewing places sell them for sterilizing equipment. 1 tablet is enough to do a gallon of otherwise safe looking water. A pack of 50 is around a dollar. [Previous page](https://boards.straightdope.com/t/how-long-does-water-stay-fresh/322020.md?page=1)