Is static water in decorative fountains a potential risk for Legionella growth?

Static water in decorative fountains is indeed a potential risk for Legionella growth. This stems from the conditions that these fountains often provide, which include standing water, a temperature range that can support bacterial growth, and nutrient-rich environments. Legionella bacteria thrive in temperatures between 20°C and 50°C (68°F to 122°F), and the water in decorative fountains can easily reach or maintain these temperatures, especially in warm or even temperate climates.

Additionally, fountains usually lack the high water turnover that can help mitigate the growth of bacteria found in more dynamic plumbing systems. The static nature of the water can allow biofilm—a slimy layer of bacteria and other microorganisms—to form, offering a further conducive environment for Legionella. Regular maintenance, including cleaning and treating the water, is paramount to reduce this risk.

While other choices suggest limited conditions under which static water in fountains might pose a risk, these conditions can exist at various times and in various climates, making it essential to view static water in decorative fountains as a general risk for Legionella growth, regardless of the season or climate.