Abstract :

Bahrain has invested in minimizing the Non-Revenue Water (NRW) since long time ago through its Electricity and Water Authority (EWA). In recent researches, it was found that the yearly total NRW in Bahrain is approximately equal to 21,535 M Gallon with a total cost of BD 71 Million. One of EWA strategic goals is to complete the 99% of all complains within 2 hours.

A queuing model is developed for each depot to find the optimum number of maintenance teams that satisfy the condition of completing 99% of received complaints within 2 hours. A survey sheet was designed to collect the required information for the model from Muharraq, Budaya and Riffa depots while the maintenance teams were responding to complaints. Due to the shift arrangement and due to the type of maintenance teams in each depot, a linear programing model is developed in order to distribute and schedule EWA and contractor maintenance teams while keeping the EWA current maintenance teams.

To validate the results, Arena simulator is used to verify whether the results obtained are practical or not by ensuring that the delay time to start serving a complaint is minimized. To evaluate the robustness of the findings with the increase of the volume of the complaints or the decrease of the number of maintenance teams, a sensitivity analysis is conducted to ensure the completion of 99% of complaints within 2 hours. The results obtained show that the objectives of this research are achieved, which indicate that a considerable reduction in the NRW can be maintained.