Hydraulic Model of District Metered Areas for Leakage Reduction in Ghana Water Company Limited: A Case Study of Dansoman DMA in Accra, Ghana

Abstract

Water distribution network models are used by water utilities extensively. A promising model is required for increasing reliability of water provision. The main intention of the study was to develop a well calibrated and validated hydraulic model and also determine the level of leakage in the DMA. It presents a hydraulic model for Dansoman District Metered Area (DMA) pipe network in Accra, which is part of the supply network operated by Ghana Water Company Limited (GWCL). The DMA serves a population of approximately 16,390 people and it covers an area of 363 hectares. Bulk flow readings were taken at inlet points. Nodal demands were allocated by calculating average uniform demand per connection. Variation in spatial distribution of population was accounted by computing the nodal influence areas by Theison polygon principle in Arc-GIS. Minimum Night Flow (MNF) measurements were taken by night flow loggers at sample points for leakage computation. The model was developed by using EPANET 2.0 and calibration of the model performed at critical moments produced a well calibrated and validated hydraulic model that presents quite closer measured and computed values with correlation coefficients between 0.66-0.98. The developed model can be used for both operations and management of water supply in the DMA. The study also found that leakage (physical water loss) in the DMA was 30.6% of the total water supplied. Therefore, the result of this study informs GWCL to implement a full scale leakage reduction action by showing how much of the water produced is being lost which could have increased the coverage and efficiency of the utility.