Integrated level of service index for buried water infrastructure: Selection and development of performance indicators.

• The urban densification is putting pressure on buried water infrastructure (BWI). • Sixty-two key performance indicators (PIs) were selected for the assessment. • A hybrid approach was adopted to aggregate the selected PIs. • An integrated level of service (ILOS) index was developed. • The ILOS index was applied to four municipalities within British Columbia, Canada. Buried water infrastructure (BWI) services (drinking water, wastewater, and stormwater) are vital for sustainable urban development, which can be impacted by increasing densification needs. This study aims to develop an integrated level of service (ILOS) index to evaluate the performance of BWI underneath the urban densification. Development of the ILOS index involved identifying and selecting key performance indicators (PIs) under the pre-defined criteria and objectives. Initially, eighty-four PIs were identified through comprehensive literature. These PIs were reduced to sixty-two, based on experts' judgment and feedback using three selection criteria and further grouped into a hierarchical structure. A hybrid approach of dynamic fuzzy cognitive maps and an ordered weighted average operator was adopted to aggregate PIs into the ILOS index using the bottom-up approach. The developed ILOS index was applied to four municipalities within British Columbia, Canada. The results show that all four municipalities need to significantly improve their BWI for sustainable growth and effective urban management. A sensitivity analysis was conducted to identify the most important PIs for the design of the ILOS index. Future research will be conducted to apply the proposed approach for better decision-making of growth scenarios, which will provide early warning changes in urban densification. [ABSTRACT FROM AUTHOR]