Inter-Utility Performance Benchmarking Model for Small-to-Medium-Sized Water Utilities: Aggregated Performance Indices

Abstract

About 95% of the water supply systems in Canada are being operated by small-to-medium-sized water utilities (SMWU) serving populations less than 50,000. The representation of these utilities in National Water and Wastewater Benchmarking Initiative (NWWBI) is almost negligible due to less awareness, issues related to data availability, and financial constraints. In the present work, an inter-utility performance benchmarking model (IU-PBM) is developed, which entails consideration of 47 performance indicators (PIs) for different functional components of SMWU, such as water resources and environment, personnel, physical assets, quality of service, water quality and public health, and financial aspects. For performance benchmarking, 47 (linear, exponential, logarithmic, and polynomial) transformation functions have been established to translate the calculated PIs into performance levels between 10 and 100, which is based on literature, NWWBI reports, and expert judgment. The weights are estimated using a specific method from the literature for ranking of PIs by different water utilities in the Okanagan basin, British Columbia, Canada, and opinions of experts working in water infrastructure management. Finally, performance indices have been established by aggregating the transformed performance levels using the technique for order preference by similarity to ideal solution (TOPSIS) (i.e., based on the concept of relative closeness to the most desirable performance and remoteness from the least desirable performance). The IU-PBM results presented in the form of a web diagram demonstrate the utility’s performance to the top management for pragmatic decision making. The proposed model has also been implemented for two SMWU operating in Okanagan Basin to evaluate its practicality.