Background losses reduction by excessive pressure cut off

摘要

It is one of the greatest challenges water utilities are facing in striving toudreduce and control Non Revenue Water (NRW) within an economic level. Whileudsupplying the population with sufficient water, the reduction of NRW has been a keyudissue in judging the performance of all water utilities. Background loss is oneudcomponent of physical losses which is the most to contribute to NRW. This studyudaimed on pressure management method conducted at a site to reduce backgroundudloss. The pressure management method used is by the installation of a PressureudReducing Valve (PRV) with timer-based pressure cut-off controller as an on-siteudverification. The BE59 - Kg. Melayu Pandan, one of the District Meter Area (DMA)udin Johor Bahru has been selected as a case study. The Step Tests are carried out toudanalyse and identify the steps with high background leakage and to find suitableudlocation for the purpose of PRV installation. The DMA meter and a data logger areudused to measure and record pressure and flow profiles to determine leakage at eachudstep and to establish leakage baselines, before and after the activation of the PRV.udThe results indicated a high reduction of background loss and given significantudimpact on the NRW level in Johor Bahru. In financial terms, volume of water savedudand the monthly expenditure shows the return of investment (R.O.I) is in a period ofud6 months. This research findings show a higher reduction on background loss can beudachieved by optimising the cut-off controller, analysing further excess pressure cutoffudbased on pressure profiles in the existing or new DMA with a PRV and controllerudin a large scale. Comparisons with other methods of pipe replacement and ActiveudLeakage Control (ALC), indicate that, the pressure management by excess pressureudcut-off is the most feasible, economical and effective method in the NRW reduction.