Designing Resilient Water Distribution Systems Under Demand Uncertainty: A Kohat City Case Study

Abstract: This study explores the impact of accurate water demand forecasting and the integration of diurnal consumption patterns on the design and efficiency of water distribution systems, particularly in Pakistan. Due to the lack of a comprehensive metering infrastructure, water demand patterns remain poorly understood, complicating optimal system design. In response, a hypothetical diurnal pattern based on Iranian water usage behaviours was adopted to simulate and assess the performance of water supply systems under varying demand scenarios. The study compares two models: one based on instantaneous peak demand and the other incorporating realistic diurnal fluctuations over a 24-hour period. Simulations revealed that designing systems based on instantaneous peak demand leads to overdesign, resulting in excessive pressure during low-demand periods, thus increasing operational costs, risking pipeline damage, and reducing system lifespan. In contrast, designing with a diurnal pattern proved to be more cost-effective, sustainable, and reliable, as it better matched actual consumption patterns. The findings emphasize the necessity of integrating dynamic pressure management, seasonal and peak demand considerations, and advanced flow regulation techniques in future infrastructure projects. These recommendations aim to enhance the sustainability and efficiency of water distribution systems, ensuring adequate water supply and equitable distribution, while minimizing resource wastage and operational inefficiencies.