Using Calcium Hypochlorite (Pool Shock) for Emergency Water Purification

When it comes to emergency preparedness, ensuring access to clean drinking water is a top priority. Many preppers rely on methods like bleach, water filters, or purification tablets, but there’s a lesser-known, long-lasting solution that can be incredibly effective: calcium hypochlorite, commonly known as Pool Shock. This chlorine-based compound is a powerful and versatile tool for water disinfection, offering a nearly indefinite shelf life, making it an ideal backup for emergencies when bleach expires, or other supplies run low.

What is Pool Shock?

Pool Shock typically contains calcium hypochlorite, a chlorine-based compound used to sanitize swimming pools by killing bacteria, viruses, and algae. Though commonly associated with pool maintenance, it’s an excellent emergency water purification tool.

Chlorine-based disinfectant: Calcium hypochlorite is effective against various waterborne threats, including bacteria, viruses, and even the giardia parasite. It can also eliminate some protozoa like Cryptosporidium, though higher concentrations or longer contact times may be required for complete effectiveness.
Recognized for emergency use: While the EPA doesn’t specifically recommend Pool Shock for water purification, calcium hypochlorite is a widely accepted method for disinfecting water during emergencies when used correctly.

Why Calcium Hypochlorite is Great for Water Purification

When compared to other methods like bleach (sodium hypochlorite), Pool Shock offers some significant advantages:

Long-lasting: Bleach loses its effectiveness after 6-12 months, making it less ideal for long-term storage. In contrast, calcium hypochlorite has an almost indefinite shelf life when stored properly in a cool, dry place.
Highly concentrated: A small amount of Pool Shock can go a long way. For example, a 1-pound (16 oz) bag of calcium hypochlorite can disinfect an incredible 16,384 gallons of water, making it a smart addition to your water purification supplies.

How to Use Pool Shock for Water Purification

Using calcium hypochlorite to purify water requires careful handling due to its chemical strength. Follow these steps to prepare a solution and treat water effectively:

To Prepare Pool Shock Solution (1 Gallon)

Add 1 level teaspoon of pool shock to 1 gallon of water.
Shake well to mix.
Label the container with “Calcium Hypochlorite” or “Pool Shock,” and tape instructions to the bottle for ease of use.

To Disinfect Water with Pool Shock Solution

Use 2/3 to 3/4 ounces of the prepared pool shock solution per gallon of water to disinfect it.
Shake well and allow the water to sit for 30 minutes before drinking.

How to Store Pool Shock

Pool Shock solution should be stored similarly to liquid bleach—keep it in a cool, dry, and dark location, and be sure to include a 1-ounce measuring device for easy use.

For Pool Shock powder, it’s important to keep it sealed in its original packaging. For added protection, place the powder in a mason jar with a tightly closed lid. Avoid storing it in areas where temperatures exceed 95°F, as this can reduce its shelf life.

What to Look for When Purchasing Pool Shock

When shopping for Pool Shock, be sure to select a product with 68% or higher calcium hypochlorite for water purification purposes. Two commonly recommended brands include HTH Ultimate Shock Treatment 7 in 1 and Ultima TKO. Ensure you’re getting the right concentration, as lower concentrations may not be as effective for disinfection.

Conclusion

In any emergency preparedness plan, having multiple options for water purification is crucial. Calcium hypochlorite, or Pool Shock, offers a cost-effective, long-lasting, and powerful alternative to bleach and other purification methods. With its ability to treat vast quantities of water and its indefinite shelf life, it’s a must-have for anyone serious about being prepared. Just be sure to handle and store it properly, and you’ll have peace of mind knowing that clean drinking water will always be within reach—even in the most challenging situations.