Does Water Expire?
I'm sitting here in the cabin looking at a 5-gallon container of water that I've had sitting here for two years. I'm drinking out of this container periodically, but it really is for long-term storage and emergency use.
It got me thinking, can water expire? This article explores what I found on water expiring and how to store it properly.
Water needs to be stored correctly to stay drinkable. Cheap plastic can leach BPAs into water over-time, especially if left in warmer temperatures. Water can also go bad or stale if you don't seal the containers properly. It's better to store in glass, ceramic, metal, or food-grade plastic. Water should be stored in a cool dark place for long term storage.
I am a little wary of using plastic for long-term storage because of the BPA Leach that can happen. But a 5-gallon glass container is a little unwieldy and hard to find. Same with metal containers. Plastic is just so cheap and attainable.
I'm going to go through some basic questions on long-term water storage and then some basic questions on water expiring in general.
Can water expire?
Water has an expiration date, but usually it's the bottle that goes bad that can lead to the water itself being contaminated. Ultimately, drinking water past the expiration date won't cause you harm.
The water inside can stay safe to drink indefinitely, but you need to be aware of the smell, taste, and coloration. If any of those things are off obviously use a filter or just drink other water if available.
If these containers are open, such as a cup left outside or in a room, is much more opportunity for dust, particles, and mold to start forming depending on the conditions of the environment. A cup untampered with sitting on a table might last a couple of days or so. Probably longer than that realistically unless you live in a nasty place.
I'm going to trust that you can use your best judgment as well as your eyes, nose, and mouth to determine whether or not the water is good for you.
Clean your Waterbottles
If you are using a sealed container, but refilling it over and over again do you want to make sure you are cleaning it consistently. I have had plenty of friends that I go adventuring with use the same bottle over and over again, not washing it, and having black mold form inside of their water bottle.
Sometimes you don't realize the black mold formed in there until it's too late. My buddy didn't die after drinking black mold, but he got a wicked sore throat. It is toxic by the way. Just wash your bottles consistently.
Storing Water for Long Term:
Storing water correctly will prevent any sort of bacteria from growing in your stockpile. Last thing you need is to show up your water supply when you need it most, and it has black mold floating around in it.
Here are a few things you should know about storing water long term:
Use Food Grade Containers
Food-grade Plastic containers are very common. For long-term storage, you are typically thinking 5 to 55 gallon drums. These are usually those black, white, or blue barrels that many people oftentimes use as rain collection on their property. This plastic is bpa-free and can store water for a long time safely.
Metal
Metal that is “enameled” is best to use. Basically it has a glaze over the surface that prevents rust and keeps items from soaking into the metal or affecting it in any way. This enamel glaze also makes it easier to clean. Think of camping cups you might find and many major sporting goods stores.
Metal is great for long term because the sunlight can’t penetrate the container, nothing leaches through metal, and it is durable.
The downside is it’s usually more expensive.
Glass
Glass is a great storage container for water. The downfall is that it's obviously the least durable of the containers. So if you are taking it back and forth every so often to get it filled up at the ol’ watering whole, it might be a safer bet to use a different container.
But glass is the cleanest way to store it and if the container is sitting in one spot it is probably the best option for long-term storage of water.
Ceramic
This material is similar to glass in many ways. The benefits are it doesn't absorb light or leach chemicals through if it has a glaze over it. Ceramic can also last thousands of years.
Storage Environment
Store water in a dark cool place but not a moldy place, for obvious reasons.
Basement, cellar, cave, or secret lair. Just keep it off of concrete as chemicals can leech through the plastic. Put it on a wood pallet or shelf. I haven’t heard of this myself but apparently storing plastic on concrete can make it tast funny
Seal the Containers Properly
A tight seal makes all the difference. The container type doesn't matter if the lid is open. Seal it tight preferably with a rubber washer on the cap and screw top. This will prevent contaminants from getting in through the opening.
Check on it every few months to make sure it doesn’t smell funky or musty.
Can Mold form in Water?
If you're using a water bottle often for your adventures, and aren't washing it properly or often, you might run into one of the most toxic mold species floating around in your water bottle.
Stachybotrys chartarum, or black mold
If you aren't cleaning your bottle often maybe you should, especially if it's going from a car, to a backpack, to a bike and being refilled over and over before cleaning.
How your long term water storage can become contaminated:
If you do the following, you can contaminate your water and potentially ruin the taste or introduce bacteria to the supply.
Opening the container often - If you drink from the water and are opening the lid often, and leaving open for periods of time there is a chance dust, debris, could enter in to the container.
Leaching - Contaminants can literally go through materials like plastic in order to affect the water. Keep it in container
Not Cleaning the container before hand - Dust and Residue from store shelves or pantry can result in poor water quality after a few months.
Will I get sick from old drinking water?
Unlikely. If it’s moldy with black mold, then yes. But most likely, it might just have a stale taste. Have you ever drank a water-bottle that sat in a car and it tasted like the car smelled? (just me?) Well, that’s the stale taste I’m talking about. Odors and chemicals leach through substances, especially plastic. But plastic is light, durable, and cheap which is why water bottles are sold in plastic.
Will water evaporate in a sealed container?
Water left in a sealed container will not evaporate through it. If you leave the lid off the container outside then yes some will evaporate.
How do I test the water to make sure it’s not contaminated?
First, use your senses to check smell, color, and taste. If stored correctly then you had nothing to worry about. But if you didn’t store it, you can check a couple of things:
Salinity - this is the saltiness or amount of salt that may be dissolved in the water. This is more for natural water source checking but may apply depending on where in the world you are.
pH - measurement of how acidic/ basic the water is. Range from 0 to 14. Less than 7 is more acidic. Greater than 7 means it’s more of a base (Soap is a base for example)
pH of water is important and more relevant. Testing this with pH strips can give you an Idea if it’s safe. Safe water for us is between 4 and 6.5. Here is a chart from USGS.gov:
Both of these apply more to natural water or water you are just unsure of. This may be important in a survival situation where you are out of options.
What if I need to drink the water and I don’t test it?
Water Filtration - This can be a life straw, container, or homemade charcoal filter. Whatever you use, the goal is to remove the impurities in water with a very fine, physical barrier to catch pathogens, rocks, dirt, algae, etc.
Use water purification tablets - These tablets do not kill toxic chemicals, but, they are made up of chemicals that kill microorganisms that can cause puking and diarrhea.
Use Bleach - I'M NOT TELLING YOU TO DRINK BLEACH. Basically, 16 drops of household bleach per gallon can cleanse the cloudy water of potential harm and is fine to drink, allegedly. Honestly, this is the least likely thing I will ever use but I read that the CDC said you could use bleach to clean water.
Conclusion
Water doesn't go bad if stored in airtight, food-grade containers in a dark and cool place.