Improving wastewater treatment plants operational efficiency and effectiveness through an integrated performance assessment system

Optimizing the efficiency of urban water systems is a growing concern for water utilities worldwide. Wastewater treatment plants (WWTP) are crucial in maintaining water quality and resource recovery in a world facing growing challenges such as climate change, water-energy-food nexus and the increase of legal requirements and users' expectations. Thus, adopting a performance assessment system (PAS) is of the utmost importance to assess operating conditions and to identify critical aspects of the WWTP which can negatively affect its effectiveness, efficiency and reliability. This paper presents the global and operational performance assessment of an urban WWTP and identifies improvement measures. The WWTP presented a good performance in terms of effectiveness and reliability. Nevertheless, in terms of efficiency, relevant improvement opportunities were identified, specifically in the sludge treatment phase and in terms of energy management. PAS was proven to be successful in the identification and prioritization of rehabilitation needs in a systematic way which will continuously improve the efficiency and effectiveness of the WWTP as well as to support asset management decisions regarding their upgrade and retrofit.