Storing a personal supply of potable water is a foundational step in emergency preparedness, providing security against utility failures or natural disasters that can disrupt municipal water services. This process requires careful selection of containers, proper disinfection, and diligent maintenance to ensure the water remains safe for consumption over extended periods. Following specific steps guards against chemical contamination and microbial growth, creating a reliable source of clean water for your household.
Selecting and Preparing Storage Containers
The choice of container is paramount for successful long-term water storage, as the material must not degrade or leach harmful substances into the water over time. The best options are containers specifically labeled as food-grade plastic, such as High-Density Polyethylene (HDPE), often identified by recycling code #2. These materials are durable and resist chemical permeation. While glass and stainless steel are also excellent non-permeable options, they are often impractical for large-volume storage due to their weight, cost, or fragility.
Avoid using containers previously used for non-food liquids, as chemical residues are nearly impossible to remove completely. Common household containers like used milk or juice jugs are also unsuitable because they are made from biodegradable plastics that break down prematurely. Use a container with a tight-fitting, screw-on lid to maintain an airtight seal, preventing recontamination and the absorption of ambient odors.
Before filling, containers must be thoroughly cleaned and sanitized to eliminate existing bacteria or debris. Begin by washing the container with soap and warm water, rinsing completely. Sanitization involves rinsing the container with a mild chlorine solution, typically one teaspoon of unscented household bleach mixed with one quart of water. This solution should coat all interior surfaces for at least 30 seconds before being poured out, and the container should then be rinsed or allowed to air-dry.
Essential Steps for Water Treatment and Filling
Even if tap water comes from a reliable municipal source already treated with chlorine, adding a small, precise amount of fresh disinfectant is necessary for indefinite storage. This prevents the regrowth of microorganisms as the residual chlorine dissipates over many months. Use regular, unscented household liquid chlorine bleach, which typically contains between 5% and 9% sodium hypochlorite. Never use color-safe, scented, or splash-less varieties, as these contain additives unsafe for consumption.
For every gallon of water you intend to store, the recommended treatment is eight drops of liquid bleach, or approximately one-half teaspoon for a five-gallon container. This ratio establishes a sufficient chlorine residual to maintain water safety without creating an overpowering taste. The bleach should be added directly to the water, mixed thoroughly by gently shaking the container, and then allowed to stand for a minimum of 30 minutes before sealing it.
After the 30-minute contact time, a slight chlorine scent should be noticeable when the container is unsealed briefly. If no chlorine odor is present, it indicates that organic material in the water has consumed all the added chlorine, and the dosage should be repeated, followed by another 15-minute wait. Once the water is properly treated, fill the container almost completely to minimize the air space, which helps prevent the water from absorbing off-flavors from the plastic. Finally, label the container with the storage date and the word “drinking water” to eliminate any confusion about its contents.
Ensuring Safe Long-Term Storage
The environment in which the water is stored significantly affects its long-term viability. Water containers should be placed in a cool, dark, and dry area where the temperature remains stable, ideally between 50°F and 70°F. Exposure to sunlight or excessive heat accelerates the degradation of plastic containers, promotes the leaching of trace chemicals, and encourages microbial growth.
It is crucial to store containers away from items that emit strong vapors, such as gasoline, paint thinners, or cleaning chemicals. Since plastic materials are slightly permeable, airborne fumes can penetrate the container walls and impart an unpleasant taste or odor. Additionally, avoid placing water containers directly on concrete floors, as the material can wick moisture and fluctuate in temperature, potentially compromising the container’s integrity.
Even with proper treatment and optimal storage conditions, the quality of home-stored tap water should not be considered permanent. Experts recommend rotating the supply and replacing the water every six months to one year to ensure maximum freshness and safety. When rotating, visually inspect the water for cloudiness or discoloration, and check for any off-odors before use. If the water appears flat when opened, it can be easily aerated by pouring it back and forth between two clean containers several times before consumption.