The relationship between sewer flood volume and receiving water quality in an integrated urban wastewater system

Abstract

This paper describes a study of the relationships between the volume of sewer flooding in urban areas and water quality in receiving waters. An integrated urban wastewater model is constructed to simulate the various water quality and hydraulic processes in the sewer system, wastewater treatment plant, and receiving water. A series of rainfall events with different return periods are derived from intensity-duration-frequency curves for simulation of a semi-hypothetical urban catchment. Results reveal a close negative, non-linear relationship between flood volume and receiving water quality represented by the minimum DO and maximum ammonium concentrations, and indicate the particular influence of rainfall intensity. This research provides a first insight into the relationship between urban flooding and river water quality required for the holistic management of water in the urban environment.