Transient Mobilisation of Replicated Biofilms

Water quality implications of transients propagating through operational networks has previously received little attention, even though there may be significant consequences. Conceptually the dynamic forces induced by hydraulic transients could mobilise microbial biofilms and release trapped hazardous material into the bulk water, potentially causing public health and economic problems. This paper presents an experiment that, for the first time, investigated repeatable and characteristic conditions of both hydraulic transients and biofilms. The controlled and systematic experiment shows that valve opening transients can mobilise replicated biofilms where steady state environments cannot. Furthermore the experiment explored the effect of hydraulic forces, both steady state and transient, on two different replicated structures of biofilms. It is vital that transients are examined in further detail to understand the mechanisms causing mobilisation, and future modelling of networks includes transients as a risk to water quality in DWDS.