An Efficiency-CentredHierarchicalMethod toAssess Performance of WastewaterTreatment Plants

Document Type: Original Research Paper


Department of Building, Civil, and Environmental Engineering, Concordia University, Montreal, Quebec,Canada H3G 1M8


An efficiency-centred hierarchical model is developed to assess the performance of
wastewater treatment plants (WWTPs). Specifically, a new treatment performance index (TPI) has
been proposed to determine the overall treatment performance of WWTP by analysing the TPI
values and the weights of individual treatment phase for overall treatment performance. Three
modules have been developed to examine the performance of the primary, secondary, and tertiary
treatment units of aWWTP. Themodel is applied to threeWWTPswith different scale, loading rate,
capacity, and process phases. The case study results indicate that the developed tool is useful in
assessing the WWTP system in terms of treatment efficiency, operating conditions, and costeffectiveness
of its management schemes. The model can be also combined with an infrastructure
condition rating index model to form a condition rating model for a WWTP, and used as a costeffective
tool to evaluate current and future needs in operation and management.