Water is essential for life, but how long can you safely store it before it becomes undrinkable? Generally, properly stored water can last indefinitely, but factors like storage conditions and container type can affect its quality and safety over time.
How Long Can Stored Water Remain Safe to Drink?
When it comes to storing water for emergencies or daily use, understanding its shelf life is crucial. Properly stored potable water in clean, sealed containers can theoretically last forever. However, the U.S. Centers for Disease Control and Prevention (CDC) and the Federal Emergency Management Agency (FEMA) recommend rotating stored water every six months to a year. This ensures optimal freshness and quality, even if the water itself doesn’t technically "go bad."
Factors Affecting Water Storage Life
Several elements influence how long your stored water remains safe and palatable. The quality of the initial water, the type of container used, and the storage environment all play significant roles.
- Initial Water Quality: Using clean, potable tap water is the best starting point. Avoid using water from questionable sources like ponds or streams unless it’s properly treated and purified before storage.
- Container Material: Food-grade plastic containers (like PET or HDPE) or glass are ideal. Avoid containers that previously held chemicals or milk, as residues can leach into the water. Ensure containers are thoroughly cleaned and rinsed before filling.
- Storage Environment: Cool, dark, and dry locations are best. Sunlight can degrade plastic containers and promote algae growth. High temperatures can also affect water quality and the integrity of the container.
Understanding "Going Bad"
Water doesn’t "go bad" in the way food spoils, developing harmful bacteria or toxins on its own if stored correctly. Instead, the concern is potential contamination over time.
If stored in a less-than-ideal container or if the seal isn’t perfect, airborne contaminants or bacteria can eventually enter. Over extended periods, especially in warm or sunny conditions, the plastic from containers can also break down, potentially leaching chemicals into the water. This is why regular rotation is advised.
Best Practices for Storing Drinking Water
To maximize the shelf life and safety of your stored water, follow these essential guidelines. These practices help prevent contamination and maintain water quality for extended periods.
Choosing the Right Containers
The type of container you use is paramount for long-term water storage. Opt for food-grade plastic containers specifically designed for water storage.
- PET (Polyethylene Terephthalate): Commonly used for single-use beverage bottles, these are generally safe for water storage but can degrade over time.
- HDPE (High-Density Polyethylene): These are more durable and often used for larger water jugs. Look for the recycling symbol #2.
- Glass: While inert and safe, glass is heavy and breakable, making it less practical for large-scale storage.
Always wash containers thoroughly with soap and water and rinse them completely before filling.
Optimal Storage Locations
Where you store your water significantly impacts its longevity. Aim for conditions that minimize degradation and contamination risks.
- Cool Temperatures: Store water in a location with a consistent temperature, ideally between 50°F and 70°F (10°C and 21°C). Avoid attics, garages, or areas prone to extreme temperature fluctuations.
- Darkness: Protect stored water from direct sunlight. UV rays can break down plastic containers and encourage the growth of microorganisms.
- Away from Contaminants: Keep water storage away from chemicals, gasoline, pesticides, and other hazardous materials. Ensure containers are tightly sealed to prevent odor absorption.
How to Prepare Water for Storage
Before filling your chosen containers, take a few steps to ensure the water is as pure as possible. This initial preparation is key to long-term safety.
- Start with Potable Water: Use clean, treated tap water. If your tap water quality is uncertain, consider using filtered or bottled water initially.
- Disinfect (Optional but Recommended): For added security, you can disinfect tap water by adding two drops of plain, unscented household bleach (5-6% sodium hypochlorite) per gallon of water. Mix well and let it sit for 30 minutes. If the water has a slight chlorine smell, it’s ready.
- Fill Containers: Fill containers to the very top, leaving no air space. This minimizes contact with oxygen, which can degrade the water over time.
- Seal Tightly: Securely cap the containers to prevent leaks and contamination.
How Often Should You Rotate Stored Water?
While water itself doesn’t expire, the containers and seals can degrade, and the water’s taste can change. Therefore, rotating your stored water supply is a recommended practice.
FEMA and the CDC suggest rotating your emergency water supply every six months. This ensures you always have fresh-tasting, safe drinking water available. When you rotate, you can use the older water for non-drinking purposes like watering plants or flushing toilets, and refill the containers with fresh water.
Signs Your Stored Water Might Be Compromised
Even with good practices, it’s wise to know what to look for. If you notice any of these signs, it’s best to discard the water and replace it.
- Cloudiness or Sediment: If the water appears cloudy or has particles floating in it, it may be contaminated.
- Unusual Odor: A musty, chemical, or otherwise off-putting smell indicates a problem.
- Altered Taste: While taste can change slightly over time, a significantly different or unpleasant taste is a warning sign.
- Damaged Container: Any cracks, leaks, or signs of degradation in the container should prompt replacement.
People Also Ask
### How much water should I store per person?
It’s recommended to store at least one gallon of water per person per day for a minimum of three days, with a preference for a two-week supply for emergencies. This includes water for drinking and sanitation purposes.
### Can I store water in milk jugs?
While milk jugs are convenient, they are not ideal for long-term water storage. They are often not made from food-grade plastic and can degrade over time, potentially leaching chemicals. It’s best to use dedicated food-grade water containers.
### Does water expire if left in a plastic bottle?
Water left in a sealed plastic bottle in cool, dark conditions can remain safe to drink for a very long time. However, plastic can degrade over extended periods, especially when exposed to heat and light, potentially affecting water quality. Rotating stored water is still advised.
### What happens if you drink old stored water?
If stored properly in food-grade containers away from light and heat, old stored water is generally safe to drink. However, if the water has become contaminated due to a faulty seal, container degradation, or poor storage conditions, drinking it