Authors

S.P. Hides, R.Y.G. Andoh and P. Carroll

Abstract

Sewer systems evolved as part of the human development process to meet the challenges of effectual draining of urbanizing areas. In the recent history of human development, following the implementation of wastewater treatment plants to control point sources, a shift occurred with wet-weather induced overflows from sanitary sewer systems (SSOs) and combined sewer systems (CSOs) being deemed to be a major cause of water quality impairment in urban streams, rivers and other receiving waters. The general move was towards separate sewers, one to convey foul water (sewage) and the other to convey the supposedly cleaner stormwater runoff to the nearest watercourse.

With the increased awareness, in more recent times, of the adverse environmental impacts of stormwater runoff and other diffuse wet-weather discharge sources, the need has arisen for stormwater control and treatment systems. There is a need now for a more holistic approach to be adopted in the development of solutions to wet-weather induced problems in the drainage of urban catchments. This paper reviews approaches to the management of urban wet-weather such as stormwater runoff, premature overflows, basement backups and flooding; outlining case examples of the successful application of non-conventional, innovative, novel and emerging approaches, techniques and devices that assist in the better management and control of inflow sources and water quality. This involves the seeking of solutions within the upstream portions of drainage and sewer systems by intercepting, containing, controlling and treating excess wet-weather flows before they cause hydraulic and water quality problems in downstream areas / sections of drainage systems.

Authors

R.Y.G. Andoh, A.J. Stephenson and P. Collins

Abstract

The need for a more holistic approach in the development of solutions to wet-weather induced problems in urban drainage systems is advocated. A review of current approaches to resolving problems of premature overflows and flooding is presented outlining a case example of the successful application of non-conventional approaches, techniques and devices that assist in the better management and control of wet-weather flow sources. This involves the seeking of solutions within the upstream portions of drainage systems by intercepting, containing, controlling and treating excess wet-weather flows before they cause hydraulic and water quality problems in downstream areas (sections of the drainage system). These approaches have been found to be more cost-effective than conventional solutions and involve the implementation of distributed/decentralised schemes which in turn offer improved opportunities for wider community and other stakeholder involvement leading to the realisation of amenity and other non-structural benefits.