Random Network Model for Assessing the Topological Performance of Water Distribution Systems

Abstract

A complex network approach enables identifying various topological characteristics of critical infrastructure such as water distribution networks (WDNs). These infrastructure networks are designed based on site-specific conditions and also change over time, so at some point, their topological properties may require improvement, especially in terms of their functions. This research aims to analyze WDNs by establishing a random network with varying proportions of grids (p g). To generate random networks, the properties of the real WDN of a city in South Korea were used as a reference point. Our results indicate that, as the WDN shifted from a loop to a branched structure, the system functioning changed non-linearly with the existence of a threshold below which a network may be effectively improved with low resource inputs. More specifically, the threshold p gs were identified as 0.40 and 0.44 for network efficiency and decentralization. Additionally, the threshold p gs were around 0.22 and 0.23 with respect to availability and normalized efficiency when vulnerability was assessed by removing 1% of nodes whereas those were 0.40 and 0.45 when 10% of nodes were removed. On the other hand, the p g of the real WDN was 0.02 which was significantly lower than the thresholds, resulting in low network efficiency, more centralization and increased vulnerability. This suggests that an increase in p g is required to improve the performance of the WDN in the target area. Our study provides a novel framework for identifying a threshold for the functioning of WDNs. This threshold can be used for designing a new network, as well as for improving existing networks for better topological performance. © 2023, Korean Society of Civil Engineers.