Domestic hot water pilot microbiome dynamics

Domestic hot water (DHW) systems constitute a complex microbial habitat. Monitoring the microbial dynamics of these systems is challenging but important, as they form a potential source for the outgrowth of waterborne pathogens (e.g., Legionella pneumophila). Currently, the practice to keep pathogen outbreaks at bay is to keep water heater temperatures higher than 60 degrees Celcius. To save energy, heat shock disinfection (40 to 70 degrees Celcius) can be an interesting alternative. The goals of this study were to investigate the effect of heat shock disinfection and usage patterns on the microbial abundance and community structure, as well as the abundance and dynamics of Legionella spp. specifically.