What is the danger of using water from a swimming pool for drinking after a major power grid failure?

In the immediate chaos following a major power grid failure, a swimming pool can look like a massive, readily available source of water. However, the question, What is the danger of using water from a swimming pool for drinking after a major power grid failure? reveals significant hidden risks that must be understood and mitigated before this water is ever consumed. While the water may seem clean, it contains chemicals designed for sanitation, not human consumption, and can rapidly become a bacterial breeding ground without active filtration.
Understanding the Mechanism
Swimming pool water is chemically treated and highly susceptible to rapid contamination once the circulation and treatment systems fail due to a power outage.
Chemical Contaminants (Short-Term): The water is heavily saturated with chlorine and often stabilized with cyanuric acid. High levels of these chemicals are irritants and can cause gastric distress, vomiting, or long-term health issues if consumed regularly.
Bacterial Proliferation (Long-Term): Without the pump circulating water and the filter removing organic matter, the pool becomes stagnant. Organic matter (leaves, insects, sunscreen) rapidly breaks down, consuming the remaining chlorine and turning the pool into a massive bacterial petri dish.
Heavy Metals: Some pool systems use copper, silver, or other metals for sanitation. These can be harmful if consumed in high, concentrated levels, especially if the water is allowed to evaporate and concentrate the metals.
Natural Strategies to Try
If the pool is your only source, it must be treated with a high degree of caution, prioritizing the least-contaminated water and maximum sterilization.
Use the Clearest Water: Take water only from the deep end of the pool, several feet below the surface, avoiding the scum line and the bottom where debris settles.
The “Wait and See” Tactic: If the power has been out for only a few hours, the water is still actively chlorinated, but the chemicals are still an issue. If the power has been out for days, the bacterial risk is paramount.
Prioritize Sterilization: Filter the pool water aggressively (even through a sand filter or cloth to remove particulates) and then boil it vigorously for a minimum of one minute. Boiling is the only way to reliably kill the bacteria and viruses that rapidly bloom in stagnant pool water.
Lifestyle Tips for Long-Term Security
The pool should be considered a last-resort, high-risk source only. Secure other, safer sources first.
Use for Non-Potable Needs: Prioritize using pool water for flushing toilets, washing clothes, and fire suppression. This conserves your safer, treated potable water.
De-Chlorination: After boiling, if the chlorine smell is still strong, allow the water to stand exposed to the air for several hours or pour it back and forth between containers to help the excess chlorine dissipate.
Filter Alternatives: Have a high-quality, activated carbon filter on hand. Carbon is excellent at removing chlorine, cyanuric acid, and some organic contaminants from the pool water.
The danger of using water from a swimming pool for drinking after a major power grid failure is very real. Reserve pool water for non-potable uses and treat it with extreme prejudice before consuming. Share your experiences in the comments—what non-potable use do you prioritize for pool water?