Methodology and Approach in Developing Flushing Routines for Efficient Water Distribution System Maintenance by Using Unidirectional Flushing

Abstract

Based on the theoretical principles on the removal of deposits from water distribution systems, an effective and efficient flushing mode – the unidirectional flushing – is presented and described. When compared with other flushing modes it is shown of an example that flushing time shortens, water demand decreases and a fast formation of new deposit layers is inhibited. This is due to the fact that flushing water is supplied from already cleaned pipe sections only when applying this mode of pipe clea ning. Consequently, there will be no additional contamination caused by flushing in mobilised material from upstream pipe sections. This mode also allows the flushing to be run with higher flow velocities resulting in a much better cleaning performance. To achieve optimum cleaning results, unidirectional flushing should be performed following a systematic routine. The approach to set-up such a systematic routine is presented including the requirements regarding definitions and detailed descriptions of the sequence of flushing steps as well as of all necessary measures, the data logging and monitoring.