Analysis and evaluation of the performance of water distribution networks using performance criteria and certain and fuzzy stability index

Water supply networks are the major infrastructures in cities and villages which are implemented for water distribution. At the moment, the networks are analyzed based on demand analysis method in which the demands at different nodes are always constant and reachable and pressure is assumed as a constraint to evaluate the system stability. Various criteria are utilized in analyzing networks of which performance criteria could be mentioned. These criteria are developed and analyzed based on binary logic. One of the greatest defects of this method is presenting unreal and insensible results at threshold values as well as having no flexibility confronting experts’ knowledge. In this study, a new method is presented that utilizes performance criteria including reliability in time, combinational reliability (elasticity, water age, and entropy), resilience and vulnerability. In this paper, a new sustainability index is developed to evaluate the water supply networks using the capabilities of membership function in fuzzy logic. The usefulness of this method is demonstrated with optimized specifications of Hanoi network. Comparison of the proposed and traditional methods show the improvement in its estimation, showing that the new approach is very effective and practical.