Managing Nighttime Pressure for Background Leakage Control in Water Distribution Networks Using Simulated Annealing

Abstract

In recent decades, the global imperative to address drinking water scarcity encourages initiatives that ensure a sustainable supply. In this context, this work presents a two-stage methodology designed to reduce background leakages in water distribution networks by controlling pressures during hours of lower water demand using pressure-reducing valves (PRVs). The first stage focuses on dividing the network into smaller structures, or modules, optimizing the topological modularity index. Here, conceptual cuts are determined at the boundaries between modules, identifying them as potential positions for the installation of PRVs. The second stage determines the quantity, optimal settings, and operational status of these valves. Focused on reducing elevated nighttime pressures, the strategy minimizes the network’s nighttime resilience index using simulated annealing for optimization. The application of this methodology to two reference networks results in different levels of PRV activity, achieving a substantial decrease in pressure and nighttime background leakage volumes, without a negative impact on peak demand hours. Water scarcity is a global challenge that requires innovative solutions to manage and conserve water resources. This study presents a two-stage method to reduce water leakages in distribution networks by managing pressure during off-peak hours, which are characterized by low demand and high system pressures. In the first stage, the network is divided into smaller sections using strategic cuts that identify optimal locations for interventions such as installing shut-off valves or pressure-reducing valves. In the second stage, the pressure-reducing valves are installed at these strategic points and initially set to be fully open. The optimization process, focused on nighttime hours, adjusts the settings to reduce excessive pressures, thus minimizing water leakages without affecting daytime water supply. Applying this methodology to reference networks has shown significant reductions in both pressure and nighttime water leaks. This approach provides practical guidelines for water utilities to improve the efficiency and sustainability of their distribution systems, addressing the broader goal of mitigating water scarcity.