Patterns in the deterioration of water quality in distribution networks with demand reduction technologies

This paper presents an analysis of the effects of demand reduction on water age in a water distribution network. It is found that certain configurations of nodal demand reductions produce disproportionately high water age. Water age is shown to be highly dependent on changes in local nodal demand, rather than bulk network characteristics. Using a nodal centrality indicator, the critical nodes for increased water age are identified as those in dead zones with low transmission flows. In effect, we show that location is important when considering demand reduction, and that small but concentrated changes are sufficient to cause significant effects. This method can therefore be used to optimise water saving efforts whilst minimizing network performance deterioration.