What is the main concern when allowing swimming during high algae growth?

The primary concern during times of high algae growth in swimming pools is the health risks it poses to swimmers. Algae, when present in large quantities, can create unsafe conditions, such as skin irritations, respiratory issues, and gastrointestinal problems if ingested. This is due to the potential for harmful bacteria or toxins to thrive in the algae-laden water, which can lead to infections or other health complications.

While it's true that algae can sometimes be harmless in small amounts, the significant growth usually indicates an imbalance in the pool's chemistry that could foster pathogens. Additionally, increased water temperature can contribute to algae blooms but is not the primary concern regarding swimmer safety directly. Similarly, while slippery surfaces can be a hazard, they are not in the same category of risk as potential health issues that arise from swimming in contaminated water. This understanding emphasizes the importance of maintaining proper water quality and addressing algae growth promptly for the safety of all pool users.