Assessment of water distribution network for Arusha city

This study investigated the water distribution system of Arusha City through hydraulic analysis and hydraulic simulation of the situation of the network. Various computerized simulation models can be used for the system optimization and the choices depend on available data. In this case EPANET2 software was used in the study. The total network length included in the hydraulic model was about 39kilometers. The model utilized simple data input such as junction or nodes elevation and their demands, pipe length and their diameters, and pipe roughness. The simulation was done dynamically with time interval of 1 hour for the duration of 24hours. Then the model was run showing the maximum pressure of 78.93meters at 03:00 hours and the minimum as 5.83meters at 19:00hours. The pipes were designed to holds pressure of up to 100meters that is why the system has break pressure tanks to maintain pressure below 100meters. Also The Ministry of Water Manual of 1983 recommend a minimum pressure of 5meters in the water distribution system, therefore the system performance is in tandem with the model. The model run successfully showing that simple models can be used for networks similar to the studied network provided the existing characteristics can be simulated. The model can predict the pressure at the nodes, and thus the flow velocity. It helps the operators to predict the system (network) performance if the situation (inputs) are known.