Dynamics Model of Bacterial Regrowth in a Laboratorial Drinking-Water Distribution Networks

In order to study the bacterial regrowth status in bulk water, a laboratorial drinking-water distribution networks was built. Bacteria in water samples were numerated by three different methods. The result indicated that viable bacteria number in drinking water got from culture method (R2A medium) is 1-3 orders of magnitude lower than the result of DVC-N.A. and DVC-CTC. Direct viable counts method could reflect the real state of bacteria in drinking water, and is more suitable for numerating the alive and total bacteria in drinking water. Free chlorine and viable bacterial regrowth dynamics model were built by EPANET. The result showed that the model could reflect the real state of drinking-water, and the predicting precision is good. The model could be used to predict the chlorine decay and bacterial regrowth in drinking-water distribution networks.