Application of decision making model for leakage reduction to economic project in water distribution systems

Abstract

Water distribution systems in Korea that are responsible for maintaining a stable supply of tap water and ensuring water quality are experiencing many problems, such as pipe leakage, corrosion, and aging of pipes. There have been many recommendations for improved pipe network assessment, diagnosis, design, operation, maintenance, etc. However, improvements to the water pipe network have been limited. Additionally, leaks in the tap water supply have caused deterioration of waterworks facilities. To solve this problem, water distribution maintenance projects have focused on rehabilitation and replacement of old water pipes using pipe installation age as a factor. Evaluation methods using hydraulic pressure, such as the demand energy ratio, did not previously exist in Korean water distribution systems. In this study, we have proposed a decision-making model that considers the economic efficiency of waterworks improvement projects, using a non-revenue water (NRW) multiple regression equation. Rather than placing priority of water distribution pipe rehabilitation and replacement projects on those systems with the oldest pipe installations, additionally we have proposed using cost benefit (C/B) and life cycle cost (LCC) analysis, which can be evaluated and qualified economically through the demand energy ratio, to set priority. As project priority changes are made according to the proposed decision-making model, it is also important optimize parameters according to specific waterworks facilities operations and management.