Today, there is a growing interest in network water quality modelling. The water quality
issues of interest relate to both dissolved and particulate substances. For dissolved
substances the main interest is in residual chlorine and (microbiological) contaminant
propagation; for particulate substances it is in sediment leading to discolouration. There is a
strong influence of flows and velocities on transport, mixing, production and decay of these
substances in the network. This imposes a different approach to demand modelling which is …