Key control handles in integrated urban wastewater systems for improving receiving water quality

ABSTRACT

There is an increasing interest in modelling and control of integrated urban wastewater systems (UWS). Nevertheless, given the multiple interactions between the sub-systems – catchment, sewer system, wastewater treatment plant (WWTP) and receiving water system – the selection of effective control handles for improving receiving water quality is a major challenge. In this paper, a systematic study to identify the most important control handles in an UWS is presented. The Benchmark Simulation Model for Urban Wastewater Systems (BSM-UWS) is selected as a virtual case-study. Morris screening is used to perform global sensitivity analysis. Results indicate that, for the BSM-UWS layout, while river dissolved oxygen quality (T_exc,DO) is influenced by multiple control handles both in the sewer system and WWTP, river un-ionized ammonia quality (T_exc,NH3) is mainly influenced by WWTP control handles. The study highlights the need to perform simulations for at least 1 year when determining key control handles for UWS.