Self-degradation of water quality in distribution networks [articol]

Abstract

In the paper is investigated the influence of water flow rates through pipelines on drinking water quality in populated areas. Water residence time in networks, for more than seven days in case of buried pipes and two days for above-ground pipes, promotes the development of biochemical systems in case of low (0.5 m/s) and very low flow velocities with detrimental consequences on drinking water quality. In this case the residual chlorine decreases below the allowed technical norm limits in the distribution pipes. The case study was conducted on the distribution network of Timişoara using the EPANET program in which the hydraulic parameters (flow, diameter, velocity, loss of head) are correlated with the water stagnation periods (residents) on pipe sections with residual chlorine allowed at every point of consumption.