Improving Water Main Asset Management with the Hydraulic Impact Factor: A Risk-Based Case Study from Sugar Land, Texas

Abstract

Water utilities struggle to manage aging infrastructure with constrained budgets. Traditional asset management depends on historical failure data, and hydraulic models analyze system performance, but these approaches often operate in isolation. This planning-oriented case study from Sugar Land, TX, presents the hydraulic impact factor (HIF), a composite planning index that integrates pressure, velocity, headloss, and water age into a single weighted score representing hydraulic stress on each pipe segment. HIF is integrated into the City of Sugar Land’s Integrated Asset Management System to refine water main replacement priorities. By adjusting a scoring-based likelihood of failure using hydraulic stress, the framework shifts capital programming from a reactive, break-driven pattern toward a proactive, risk-based approach. In the Sugar Land application, HIF adjusted benefit–cost prioritization (BCP) scores for 94.5% of the portfolio, increasing the mean BCP score by 24.4% and reshuffling 39 of the top 50 and 71 of the top 100 prioritized assets. The revised rankings advanced hydraulically stressed mains into earlier capital plan years while maintaining overall portfolio stability as confirmed by a Spearman rank correlation of 0.889 and sensitivity analysis across 200 Monte Carlo weight combinations. The results indicate that the HIF framework can help utilities direct limited capital toward mains with combined deterioration and hydraulic vulnerability, supporting asset life extension, regulatory compliance, and service reliability.