Water and biofilm microbial ecology at the outlet of a storage tank in a drinking water distribution network
Microbial proliferation can lead to deterioration in the organoleptic properties of water (colour, odour, taste) and can be the cause of epidemics linked to pathogenic bacteria. Water storage tanks are also exposed to risks of external contamination through their access points and vents. They require regular monitoring and maintenance; re-chlorination at their outlet is generally recommended.Regulatory analyses of drinking water are based solely on planktonic culturable microorganisms, which are known to represent a minority of all microorganisms present (Douterelo et al. 2014). It is also important to analyse microorganisms using culture-independent approaches, such as flow cytometry or molecular biology, and not to limit oneself to planktonic microorganisms, but also to analyse biofilms (Pavanello et al. 2011, Claveau et al. 2024).In this study, the microbial ecology of water and biofilm was analysed at the outlet of a water storage tank in a drinking water distribution network in the Paris suburbs. Complementary analytical approaches of flow cytometry, agar culture, molecular biology and scanning electron microscopy allowed to compare the microbiota of water and biofilm during winter.