The effect of uncertainties on the performance of real-time control of urban drainage systems

Abstract

REAL-time control (RTC) is a technique used to dynamically control urban drainage systems to utilise the existing infrastructuremore optimally. It can be used to achieve a number of objectives aiming to improve the functioning of the urban drainage system, typically through the reduction of pollution. When heavy rainfall occurs, combined sewer systems (CSSs) can cause combined sewer overflows (CSOs) to discharge diluted, yet untreated, wastewater into receiving water bodies. These discharges can lead to ecological damage and pose a public health hazard, resulting in more stringent legislation necessitating the reduction of CSO discharges. To achieve this, expensive upgrades to the urban drainage system (UDS) have traditionally been used. RTC can reduce or negate the need for these expensive upgrades by fully utilising the existing infrastructure. RTC increasingly relies on more complex algorithms and data streams due to the rise of cheaper computing power and sensors, leading to a better understanding of the systems and more potential for dynamic optimisation. Uncertainties (inherent to modelling and monitoring exercises) can affect the functioning of these RTC procedures, but the influence of uncertainty on the performance of RTC procedures is poorly understood. This is an often quoted reason against the implementation of RTC strategies as a whole. The aim of this thesis is therefore to increase the understanding of how uncertainties can affect the performance of RTC procedures. Using three case studies (urban drainage systems of WWTP Eindhoven, Hoogvliet and Dokhaven) and both heuristic and real-time optimisation procedures, this aimwas assessed.